Investments - ISLP Schedule of Investments (Details) € in Thousands, £ in Thousands, kr in Thousands, kr in Thousands, $ in Thousands, $ in Thousands, $ in Thousands |
9 Months Ended | 12 Months Ended | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Sep. 30, 2022
USD ($)
|
Dec. 31, 2021
USD ($)
|
Sep. 30, 2022
AUD ($)
|
Sep. 30, 2022
EUR (€)
|
Sep. 30, 2022
GBP (£)
|
Sep. 30, 2022
CAD ($)
|
Sep. 30, 2022
DKK (kr)
|
Sep. 30, 2022
NOK (kr)
|
Dec. 31, 2021
AUD ($)
|
Dec. 31, 2021
EUR (€)
|
Dec. 31, 2021
GBP (£)
|
Dec. 31, 2021
CAD ($)
|
Dec. 31, 2021
DKK (kr)
|
Dec. 31, 2021
NOK (kr)
|
|
| Investments | ||||||||||||||
| Investments, amortized cost | $ 2,356,143 | $ 2,311,384 | ||||||||||||
| Investments at fair value | $ 2,293,522 | $ 2,289,105 | ||||||||||||
| Investment, Identifier [Axis]: 9 Story Media Group Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Nine Story Media Group Inc [Member] | Nine Story Media Group Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production |
| Investment, Identifier [Axis]: 9 Story Media Group Inc. First Lien Senior Secured Loan Cdor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.50% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.03% | 6.25% | 9.03% | 9.03% | 9.03% | 9.03% | 9.03% | 9.03% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Principal/Shares | $ 1,295 | $ 72 | ||||||||||||
| Investments, amortized cost | $ 1,004 | 54 | ||||||||||||
| Investments at fair value | $ 937 | $ 57 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Nine Story Media Group Inc [Member] | Nine Story Media Group Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember |
| Investment, Identifier [Axis]: 9 Story Media Group Inc. First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 5.83% | 5.25% | 5.83% | 5.83% | 5.83% | 5.83% | 5.83% | 5.83% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Principal/Shares | € | € 586 | € 39 | ||||||||||||
| Investments, amortized cost | $ 621 | 45 | ||||||||||||
| Investments at fair value | $ 573 | € 44 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Nine Story Media Group Inc [Member] | Nine Story Media Group Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| Investment, Identifier [Axis]: A&R Logistics, Inc First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 8.35% | 7.00% | 8.35% | 8.35% | 8.35% | 8.35% | 8.35% | 8.35% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 |
| Principal/Shares | $ 2,066 | $ 2,815 | ||||||||||||
| Investments, amortized cost | 1,954 | 2,748 | ||||||||||||
| Investments at fair value | $ 2,066 | $ 2,815 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLogisticsIncMember | bcsf:ARLogisticsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: A&R Logistics, Inc First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 8.23% | 7.00% | 8.23% | 8.23% | 8.23% | 8.23% | 8.23% | 8.23% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 |
| Principal/Shares | $ 5,928 | $ 43,092 | ||||||||||||
| Investments, amortized cost | 5,881 | 42,527 | ||||||||||||
| Investments at fair value | $ 5,928 | $ 43,092 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLogisticsIncMember | bcsf:ARLogisticsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: A&R Logistics, Inc First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 8.23% | 7.00% | 8.23% | 8.23% | 8.23% | 8.23% | 8.23% | 8.23% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 |
| Principal/Shares | $ 2,405 | $ 2,423 | ||||||||||||
| Investments, amortized cost | 2,379 | 2,391 | ||||||||||||
| Investments at fair value | $ 2,405 | $ 2,423 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLogisticsIncMember | bcsf:ARLogisticsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: A&R Logistics, Inc First Lien Senior Secured Loan 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 9.71% | 7.00% | 9.71% | 9.71% | 9.71% | 9.71% | 9.71% | 9.71% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 |
| Principal/Shares | $ 32,064 | $ 5,974 | ||||||||||||
| Investments, amortized cost | 31,731 | 5,916 | ||||||||||||
| Investments at fair value | $ 32,064 | $ 5,974 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLogisticsIncMember | bcsf:ARLogisticsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: A&R Logistics, Inc First Lien Senior Secured Loan 4 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Interest rate | 8.73% | 7.50% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Maturity date | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 |
| Principal/Shares | $ 2,695 | $ 2,716 | ||||||||||||
| Investments, amortized cost | 2,679 | 2,695 | ||||||||||||
| Investments at fair value | $ 2,695 | $ 2,716 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLogisticsIncMember | bcsf:ARLogisticsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: A&R Logistics, Inc First Lien Senior Secured Loan 5 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | |||||||
| Interest rate | 9.23% | 9.23% | 9.23% | 9.23% | 9.23% | 9.23% | 9.23% | |||||||
| Maturity date | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | May 05, 2025 | |||||||
| Principal/Shares | $ 1,319 | |||||||||||||
| Investments, amortized cost | 1,306 | |||||||||||||
| Investments at fair value | $ 1,319 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLogisticsIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: ACAMS Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,337 | |||||||||||||
| Investments, amortized cost | 3,337 | |||||||||||||
| Investments at fair value | $ 3,309 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ACAMSMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: ACM dcBLOX LLC Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,822 | |||||||||||||
| Investments, amortized cost | 3,851 | |||||||||||||
| Investments at fair value | $ 4,130 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ACMdcBLOXLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Identifier [Axis]: ADT Pizza, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 6,720 | $ 6,720 | ||||||||||||
| Investments, amortized cost | 6,720 | 6,720 | ||||||||||||
| Investments at fair value | $ 14,581 | $ 19,527 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ADTPizzaLLCMember | bcsf:ADTPizzaLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Equity Securities [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] | Beverage Food And Tobacco Sector Non-controlled Affiliate Investments [Member] |
| Investment, Identifier [Axis]: AMCP Clean Acquisition Company, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Interest rate | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | |||||||
| Maturity date | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | |||||||
| Principal/Shares | $ 16,297 | |||||||||||||
| Investments, amortized cost | 16,174 | |||||||||||||
| Investments at fair value | $ 13,222 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AMCPCleanAcquisitionCompanyLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: AMCP Clean Acquisition Company, LLC First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Interest rate | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | |||||||
| Maturity date | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | |||||||
| Principal/Shares | $ 3,944 | |||||||||||||
| Investments, amortized cost | 3,914 | |||||||||||||
| Investments at fair value | $ 3,198 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AMCPCleanAcquisitionCompanyLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: AMCP Clean Acquisition Company, LLC First Lien Senior Secured Loan - Delayed Draw Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Interest rate | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | |||||||
| Maturity date | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | |||||||
| Principal/Shares | $ 3,816 | |||||||||||||
| Investments, amortized cost | 3,810 | |||||||||||||
| Investments at fair value | $ 3,189 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AMCPCleanAcquisitionCompanyLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: AMCP Clean Acquisition Company, LLC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Interest rate | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | |||||||
| Maturity date | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | Jul. 10, 2025 | |||||||
| Principal/Shares | $ 15,767 | |||||||||||||
| Investments, amortized cost | 15,747 | |||||||||||||
| Investments at fair value | $ 13,176 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AMCPCleanAcquisitionCompanyLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: AMI US Holdings Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.50% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 7.81% | 6.50% | 7.81% | 7.81% | 7.81% | 7.81% | 7.81% | 7.81% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 | Apr. 01, 2025 |
| Principal/Shares | $ 3,866 | $ 12,892 | ||||||||||||
| Investments, amortized cost | 3,830 | 12,735 | ||||||||||||
| Investments at fair value | $ 3,866 | $ 12,892 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AMIUSHoldingsIncMember | bcsf:AMIUSHoldingsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: AMI US Holdings Inc. First Lien Senior Secured Loan - Revolver Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 5.35% | 5.35% | 5.35% | 5.35% | 5.35% | 5.35% | 5.35% | |||||||
| Maturity date | Apr. 01, 2024 | Apr. 01, 2024 | Apr. 01, 2024 | Apr. 01, 2024 | Apr. 01, 2024 | Apr. 01, 2024 | Apr. 01, 2024 | |||||||
| Principal/Shares | $ 698 | |||||||||||||
| Investments, amortized cost | 682 | |||||||||||||
| Investments at fair value | $ 698 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AMIUSHoldingsIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: AQ Software Corporation Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | $ 1 | ||||||||||||
| Investments, amortized cost | 1,107 | 1,029 | ||||||||||||
| Investments at fair value | $ 1,104 | $ 1,029 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AQSoftwareCorporationMember | bcsf:AQSoftwareCorporationMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: AQ Software Corporation Preferred Equity 1 | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2 | $ 2 | ||||||||||||
| Investments, amortized cost | 1,844 | 1,715 | ||||||||||||
| Investments at fair value | $ 1,839 | $ 1,715 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AQSoftwareCorporationMember | bcsf:AQSoftwareCorporationMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: AQ Software Corporation Preferred Equity 2 | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | |||||||||||||
| Investments, amortized cost | 507 | |||||||||||||
| Investments at fair value | $ 506 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AQSoftwareCorporationMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: ARL Holdings, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 445 | |||||||||||||
| Investments, amortized cost | 445 | |||||||||||||
| Investments at fair value | $ 575 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLHoldingsLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Identifier [Axis]: ARL Holdings, LLC Equity Interest 1 | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 0 | $ 9 | ||||||||||||
| Investments, amortized cost | 445 | 9 | ||||||||||||
| Investments at fair value | $ 619 | $ 81 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLHoldingsLLCMember | bcsf:ARLHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Identifier [Axis]: ARL Holdings, LLC Equity Interest 2 | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 9 | |||||||||||||
| Investments, amortized cost | 9 | |||||||||||||
| Investments at fair value | $ 334 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ARLHoldingsLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Identifier [Axis]: ASP-r-pac Acquisition Co LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | |||||||
| Principal/Shares | $ 27,339 | |||||||||||||
| Investments, amortized cost | 26,793 | |||||||||||||
| Investments at fair value | $ 26,792 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ASP-r-pacAcquisitionCoLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: ASP-r-pac Acquisition Co LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 |
| Principal/Shares | $ 651 | |||||||||||||
| Investments, amortized cost | 586 | |||||||||||||
| Investments at fair value | $ (24) | $ 586 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ASP-r-pacAcquisitionCoLLCMember | bcsf:ASP-r-pacAcquisitionCoLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: ASP-r-pac Acquisition Co LLC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | Dec. 29, 2027 | |||||||
| Principal/Shares | $ 4,093 | |||||||||||||
| Investments, amortized cost | 4,041 | |||||||||||||
| Investments at fair value | $ 4,063 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ASP-r-pacAcquisitionCoLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Abracon Group Holding, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2 | |||||||||||||
| Investments, amortized cost | 1,833 | |||||||||||||
| Investments at fair value | $ 3,282 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AbraconGroupHoldingLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | |||||||
| Investment, Identifier [Axis]: Abracon Group Holding, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 5.25% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 7.86% | 6.25% | 7.86% | 7.86% | 7.86% | 7.86% | 7.86% | 7.86% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Jul. 06, 2028 | Jul. 18, 2024 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 |
| Principal/Shares | $ 11,547 | $ 35,363 | ||||||||||||
| Investments, amortized cost | 11,322 | 35,270 | ||||||||||||
| Investments at fair value | $ 11,315 | $ 35,363 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AbraconGroupHoldingLLCMember | bcsf:AbraconGroupHoldingLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Abracon Group Holding, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jul. 06, 2028 | Jul. 18, 2024 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 | Jul. 18, 2024 |
| Investments at fair value | $ (40) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AbraconGroupHoldingLLCMember | bcsf:AbraconGroupHoldingLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale |
| Investment, Identifier [Axis]: Abracon Group Holding, LLC. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | |||||||
| Investments at fair value | $ (50) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AbraconGroupHoldingLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Access First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | |||||||
| Principal/Shares | £ | £ 3,217 | |||||||||||||
| Investments, amortized cost | $ 3,318 | |||||||||||||
| Investments at fair value | $ 3,483 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Access [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Access First Lien Senior Secured Loan Sonia | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | |||||||
| Maturity date | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | Jun. 02, 2029 | |||||||
| Principal/Shares | £ | £ 7,960 | |||||||||||||
| Investments, amortized cost | $ 9,770 | |||||||||||||
| Investments at fair value | $ 8,801 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Access [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Aimbridge Acquisition Co., Inc. Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Interest rate | 10.06% | 10.06% | 10.06% | 10.06% | 10.06% | 10.06% | 10.06% | |||||||
| Maturity date | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | |||||||
| Principal/Shares | $ 14,193 | |||||||||||||
| Investments, amortized cost | 13,906 | |||||||||||||
| Investments at fair value | $ 13,413 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AimbridgeAcquisitionCoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Aimbridge Acquisition Co., Inc. Second Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Interest rate | 7.59% | 7.59% | 7.59% | 7.59% | 7.59% | 7.59% | 7.59% | |||||||
| Maturity date | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | Feb. 01, 2027 | |||||||
| Principal/Shares | $ 20,193 | |||||||||||||
| Investments, amortized cost | 19,772 | |||||||||||||
| Investments at fair value | $ 18,679 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AimbridgeAcquisitionCoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Allworth Financial Group, L.P. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 5.00% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% |
| Interest rate | 7.88% | 6.00% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Maturity date | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 |
| Principal/Shares | $ 1,509 | $ 10,037 | ||||||||||||
| Investments, amortized cost | 1,493 | 9,908 | ||||||||||||
| Investments at fair value | $ 1,509 | $ 10,037 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AllworthFinancialGroupLPMember | bcsf:AllworthFinancialGroupLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Allworth Financial Group, L.P. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 5.00% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% |
| Interest rate | 7.88% | 6.00% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Maturity date | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 |
| Principal/Shares | $ 876 | $ 2,528 | ||||||||||||
| Investments, amortized cost | 863 | 2,476 | ||||||||||||
| Investments at fair value | $ 876 | $ 2,528 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AllworthFinancialGroupLPMember | bcsf:AllworthFinancialGroupLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Allworth Financial Group, L.P. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AllworthFinancialGroupLPMember | bcsf:AllworthFinancialGroupLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance |
| Investment, Identifier [Axis]: American Trailer Rental Group Subordinated Debt | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Interest rate | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% |
| Maturity date | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 |
| Principal/Shares | $ 4,973 | $ 4,913 | ||||||||||||
| Investments, amortized cost | 4,909 | 4,842 | ||||||||||||
| Investments at fair value | $ 4,973 | $ 4,913 | ||||||||||||
| PIK | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AmericanTrailerRentalGroupMember | bcsf:AmericanTrailerRentalGroupMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: American Trailer Rental Group Subordinated Debt 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Interest rate | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% |
| Maturity date | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 |
| Principal/Shares | $ 15,344 | $ 15,114 | ||||||||||||
| Investments, amortized cost | 15,053 | 14,793 | ||||||||||||
| Investments at fair value | $ 15,344 | $ 15,114 | ||||||||||||
| PIK | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AmericanTrailerRentalGroupMember | bcsf:AmericanTrailerRentalGroupMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: American Trailer Rental Group Subordinated Debt 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | |||||||
| Interest rate | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | 11.00% | |||||||
| Maturity date | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | Dec. 01, 2027 | |||||||
| Principal/Shares | $ 19,161 | |||||||||||||
| Investments, amortized cost | 18,772 | |||||||||||||
| Investments at fair value | $ 19,161 | |||||||||||||
| PIK | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AmericanTrailerRentalGroupMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | Subordinated Debt | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Amspec Services, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.42% | 6.75% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 |
| Principal/Shares | $ 2,784 | $ 43,207 | ||||||||||||
| Investments, amortized cost | 2,763 | 42,923 | ||||||||||||
| Investments at fair value | $ 2,784 | $ 43,207 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Amspec Services Inc [Member] | Amspec Services Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Amspec Services, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | |||||||
| Principal/Shares | $ 1,488 | |||||||||||||
| Investments, amortized cost | 1,457 | |||||||||||||
| Investments at fair value | $ 1,487 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Amspec Services Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Amspec Services, Inc. First Lien Senior Secured Loan - Revolver Prime Rate | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | |||||||
| Principal/Shares | $ 567 | |||||||||||||
| Investments, amortized cost | 546 | |||||||||||||
| Investments at fair value | $ 567 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Amspec Services Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | |||||||
| Investment, Identifier [Axis]: Amspec Services, Inc. First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.42% | 6.75% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 | Jul. 02, 2024 |
| Principal/Shares | $ 33,076 | $ 2,798 | ||||||||||||
| Investments, amortized cost | 32,922 | 2,768 | ||||||||||||
| Investments at fair value | $ 33,076 | $ 2,798 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Amspec Services Inc [Member] | Amspec Services Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] | Energy Oil And Gas [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Ansett Aviation Training First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.69% | 4.69% | 4.69% | 4.69% | 4.69% | 4.69% | 4.69% | |||||||
| Interest rate | 5.69% | 5.69% | 5.69% | 5.69% | 5.69% | 5.69% | 5.69% | |||||||
| Maturity date | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | |||||||
| Principal/Shares | $ 7,072 | |||||||||||||
| Investments, amortized cost | $ 5,308 | |||||||||||||
| Investments at fair value | $ 4,525 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AnsettAviationTrainingMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | |||||||
| Investment, Identifier [Axis]: Ansett Aviation Training Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 5,119 | |||||||||||||
| Investments, amortized cost | 3,842 | |||||||||||||
| Investments at fair value | $ 3,277 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AnsettAviationTrainingMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Identifier [Axis]: Ansira Holdings, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 9.31% | 9.31% | 9.31% | 9.31% | 9.31% | 9.31% | 9.31% | |||||||
| Maturity date | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | |||||||
| Principal/Shares | $ 41,731 | |||||||||||||
| Investments, amortized cost | 40,925 | |||||||||||||
| Investments at fair value | $ 20,866 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Ansira Holdings Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Ansira Holdings, Inc. First Lien Senior Secured Loan - Delayed Draw Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Interest rate | 9.57% | 7.50% | 9.57% | 9.57% | 9.57% | 9.57% | 9.57% | 9.57% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Maturity date | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 |
| Principal/Shares | $ 5,064 | $ 4,873 | ||||||||||||
| Investments, amortized cost | 5,066 | 4,874 | ||||||||||||
| Investments at fair value | $ 2,532 | $ 3,862 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Ansira Holdings Inc [Member] | Ansira Holdings Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Ansira Holdings, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.79% | 8.79% | 8.79% | 8.79% | 8.79% | 8.79% | 8.79% | |||||||
| Maturity date | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | |||||||
| Principal/Shares | $ 5,383 | |||||||||||||
| Investments, amortized cost | 5,383 | |||||||||||||
| Investments at fair value | $ 1,842 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Ansira Holdings Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Ansira Holdings, Inc. First Lien Senior Secured Loan - Revolver Prime | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 7.41% | 7.41% | 7.41% | 7.41% | 7.41% | 7.41% | 7.41% | |||||||
| Maturity date | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | |||||||
| Principal/Shares | $ 5,383 | |||||||||||||
| Investments, amortized cost | 5,383 | |||||||||||||
| Investments at fair value | $ 3,913 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Ansira Holdings Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | |||||||
| Investment, Identifier [Axis]: Ansira Holdings, Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Maturity date | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | Dec. 20, 2024 | |||||||
| Principal/Shares | $ 40,086 | |||||||||||||
| Investments, amortized cost | 40,057 | |||||||||||||
| Investments at fair value | $ 31,768 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Ansira Holdings Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Ap Plastic Group Llc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 7.87% | 7.87% | 7.87% | 7.87% | 7.87% | 7.87% | 7.87% | |||||||
| Maturity date | Aug. 10, 2028 | Aug. 10, 2028 | Aug. 10, 2028 | Aug. 10, 2028 | Aug. 10, 2028 | Aug. 10, 2028 | Aug. 10, 2028 | |||||||
| Principal/Shares | $ 7,306 | |||||||||||||
| Investments, amortized cost | 7,087 | |||||||||||||
| Investments at fair value | $ 7,014 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ApPlasticsGroupLlcMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Apollo Intelligence Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 32 | |||||||||||||
| Investments, amortized cost | 3,162 | |||||||||||||
| Investments at fair value | $ 3,182 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Apollo Intelligence [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Identifier [Axis]: Apollo Intelligence First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.26% | 8.26% | 8.26% | 8.26% | 8.26% | 8.26% | 8.26% | |||||||
| Maturity date | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | |||||||
| Principal/Shares | $ 15,425 | |||||||||||||
| Investments, amortized cost | 15,277 | |||||||||||||
| Investments at fair value | $ 15,271 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Apollo Intelligence [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Apollo Intelligence First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | |||||||
| Investments at fair value | $ (96) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Apollo Intelligence [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Identifier [Axis]: Apollo Intelligence First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | |||||||
| Investments at fair value | $ (72) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Apollo Intelligence [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Identifier [Axis]: Applitools First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | |||||||
| Maturity date | May 25, 2029 | May 25, 2029 | May 25, 2029 | May 25, 2029 | May 25, 2029 | May 25, 2029 | May 25, 2029 | |||||||
| Principal/Shares | $ 24,696 | |||||||||||||
| Investments, amortized cost | 24,460 | |||||||||||||
| Investments at fair value | $ 24,449 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Applitools [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Applitools First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | May 25, 2028 | May 25, 2028 | May 25, 2028 | May 25, 2028 | May 25, 2028 | May 25, 2028 | May 25, 2028 | |||||||
| Investments at fair value | $ (34) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Applitools [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Appriss Holdings, Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2,136 | $ 2,136 | ||||||||||||
| Investments, amortized cost | 1,606 | 1,606 | ||||||||||||
| Investments at fair value | $ 1,505 | $ 1,552 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Appriss Holdings Inc [Member] | Appriss Holdings Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | Common Stock [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: Appriss Holdings, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | |||||||
| Interest rate | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | |||||||
| Maturity date | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | |||||||
| Principal/Shares | $ 11,292 | |||||||||||||
| Investments, amortized cost | 11,081 | |||||||||||||
| Investments at fair value | $ 11,179 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Appriss Holdings Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Appriss Holdings, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 |
| Investments at fair value | $ (13) | $ (8) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Appriss Holdings Inc [Member] | Appriss Holdings Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: Appriss Holdings, Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | |||||||
| Interest rate | 9.93% | 9.93% | 9.93% | 9.93% | 9.93% | 9.93% | 9.93% | |||||||
| Maturity date | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | May 06, 2027 | |||||||
| Principal/Shares | $ 11,278 | |||||||||||||
| Investments, amortized cost | 11,092 | |||||||||||||
| Investments at fair value | $ 11,081 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Appriss Holdings Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Aptus 1724 Gmbh First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | |||||||
| Maturity date | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | |||||||
| Principal/Shares | $ 4,971 | |||||||||||||
| Investments, amortized cost | 4,971 | |||||||||||||
| Investments at fair value | $ 4,909 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Aptus1724GmbhMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Aptus 1724 Gmbh First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | |||||||
| Principal/Shares | € | € 4,162 | |||||||||||||
| Investments, amortized cost | € | 5,055 | |||||||||||||
| Investments at fair value | € | € 4,732 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Aptus1724GmbhMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Aptus 1724 Gmbh First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | |||||||
| Principal/Shares | $ 14,971 | |||||||||||||
| Investments, amortized cost | 14,971 | |||||||||||||
| Investments at fair value | $ 14,971 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Aptus1724GmbhMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Aramsco, Inc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 8.37% | 5.35% | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | 5.35% | 5.35% | 5.35% | 5.35% | 5.35% | 5.35% |
| Maturity date | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 |
| Principal/Shares | $ 14,103 | $ 23,796 | ||||||||||||
| Investments, amortized cost | 13,979 | 23,537 | ||||||||||||
| Investments at fair value | $ 14,103 | $ 23,796 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Aramsco Inc [Member] | Aramsco Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Aramsco, Inc First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | |||||||
| Maturity date | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 | Aug. 28, 2024 |
| Principal/Shares | $ 226 | |||||||||||||
| Investments, amortized cost | 201 | |||||||||||||
| Investments at fair value | $ 226 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Aramsco Inc [Member] | Aramsco Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Armor Group, LP Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 10 | $ 10 | ||||||||||||
| Investments, amortized cost | 1,012 | 1,012 | ||||||||||||
| Investments at fair value | $ 2,086 | $ 2,131 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ArmorGroupLPMember | bcsf:ArmorGroupLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Equity Securities [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale |
| Investment, Identifier [Axis]: Armstrong Bidco Limited First Lien Senior Secured Loan Sonia | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Maturity date | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | |||||||
| Principal/Shares | $ 56 | |||||||||||||
| Investments, amortized cost | 78 | |||||||||||||
| Investments at fair value | $ 76 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ArmstrongBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Armstrong Bidco T/L First Lien Senior Secured Loan Sonia | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | |||||||
| Maturity date | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | |||||||
| Principal/Shares | € | € 705 | |||||||||||||
| Investments, amortized cost | € | 763 | |||||||||||||
| Investments at fair value | € | € 954 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Armstrong Bidco T/L | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Avalon Acquiror, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.80% | 9.80% | 9.80% | 9.80% | 9.80% | 9.80% | 9.80% | |||||||
| Maturity date | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | |||||||
| Principal/Shares | $ 24,660 | |||||||||||||
| Investments, amortized cost | 24,431 | |||||||||||||
| Investments at fair value | $ 24,229 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Avalon Acquiror, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Avalon Acquiror, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.38% | 9.38% | 9.38% | 9.38% | 9.38% | 9.38% | 9.38% | |||||||
| Maturity date | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | |||||||
| Principal/Shares | $ 1,050 | |||||||||||||
| Investments, amortized cost | 878 | |||||||||||||
| Investments at fair value | $ 903 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Avalon Acquiror, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: BCC Jetstream Holdings Aviation (Off I), LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 11,863 | $ 11,863 | ||||||||||||
| Investments, amortized cost | 11,863 | 11,863 | ||||||||||||
| Investments at fair value | $ 10,209 | $ 10,563 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BCCJetstreamHoldingsAviationOnIILLCMember | bcsf:BCCJetstreamHoldingsAviationOffILLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Identifier [Axis]: BCC Jetstream Holdings Aviation (On II), LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,116 | $ 1,116 | ||||||||||||
| Investments, amortized cost | $ 1,116 | $ 1,116 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BCCJetstreamHoldingsAviationOnIILLCMember | bcsf:BCCJetstreamHoldingsAviationOnIILLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Identifier [Axis]: BCC Jetstream Holdings Aviation (On II), LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Maturity date | Jun. 02, 2023 | Jun. 02, 2022 | Jun. 02, 2023 | Jun. 02, 2023 | Jun. 02, 2023 | Jun. 02, 2023 | Jun. 02, 2023 | Jun. 02, 2023 | Jun. 02, 2022 | Jun. 02, 2022 | Jun. 02, 2022 | Jun. 02, 2022 | Jun. 02, 2022 | Jun. 02, 2022 |
| Principal/Shares | $ 8,013 | $ 7,377 | ||||||||||||
| Investments, amortized cost | 8,013 | 7,377 | ||||||||||||
| Investments at fair value | $ 6,399 | $ 6,627 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BCCJetstreamHoldingsAviationOnIILLCMember | bcsf:BCCJetstreamHoldingsAviationOnIILLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: BCC Middle Market CLO 2018-1, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Oct. 20, 2030 | Oct. 20, 2030 | Oct. 20, 2030 | Oct. 20, 2030 | Oct. 20, 2030 | Oct. 20, 2030 | Oct. 20, 2030 | |||||||
| Principal/Shares | $ 25,635 | |||||||||||||
| Investments, amortized cost | 24,051 | |||||||||||||
| Investments at fair value | $ 22,298 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BCCMiddleMarketCLO2018-1LLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance Non Controlled Affiliate | Fire Finance Non Controlled Affiliate | Fire Finance Non Controlled Affiliate | Fire Finance Non Controlled Affiliate | Fire Finance Non Controlled Affiliate | Fire Finance Non Controlled Affiliate | Fire Finance Non Controlled Affiliate | |||||||
| Investment, Identifier [Axis]: Bain Capital Senior Loan Program, LLC Equity Interest Investment Vehicles | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 5,594 | |||||||||||||
| Investments, amortized cost | 5,594 | |||||||||||||
| Investments at fair value | $ 4,063 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Bain Capital Senior Loan Program L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | |||||||
| Investment, Identifier [Axis]: Bain Capital Senior Loan Program, LLC Preferred Equity Interest Investment Vehicles | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 10 | |||||||||||||
| Investments, amortized cost | 10 | |||||||||||||
| Investments at fair value | $ (433) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Bain Capital Senior Loan Program L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:PreferredEquityInterestInvestmentVehiclesMember | bcsf:PreferredEquityInterestInvestmentVehiclesMember | bcsf:PreferredEquityInterestInvestmentVehiclesMember | bcsf:PreferredEquityInterestInvestmentVehiclesMember | bcsf:PreferredEquityInterestInvestmentVehiclesMember | bcsf:PreferredEquityInterestInvestmentVehiclesMember | bcsf:PreferredEquityInterestInvestmentVehiclesMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | |||||||
| Investment, Identifier [Axis]: Bain Capital Senior Loan Program, LLC Subordinated Note Investment Vehicles | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Dec. 27, 2033 | Dec. 27, 2033 | Dec. 27, 2033 | Dec. 27, 2033 | Dec. 27, 2033 | Dec. 27, 2033 | Dec. 27, 2033 | |||||||
| Principal/Shares | $ 50,995 | |||||||||||||
| Investments, amortized cost | 50,995 | |||||||||||||
| Investments at fair value | $ 50,995 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Bain Capital Senior Loan Program L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | |||||||
| Investment, Identifier [Axis]: Batteries Plus Holding Corporation First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Interest rate | 9.87% | 9.87% | 9.87% | 9.87% | 9.87% | 9.87% | 9.87% | |||||||
| Maturity date | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | |||||||
| Principal/Shares | $ 18,172 | |||||||||||||
| Investments, amortized cost | 18,172 | |||||||||||||
| Investments at fair value | $ 18,172 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Batteries Plus Holding Corporation [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Batteries Plus Holding Corporation First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | |||||||
| Maturity date | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | |||||||
| Principal/Shares | $ 2,038 | |||||||||||||
| Investments, amortized cost | 2,037 | |||||||||||||
| Investments at fair value | $ 2,038 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Batteries Plus Holding Corporation [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | |||||||
| Investment, Identifier [Axis]: Batteries Plus Holding Corporation First Lien Senior Secured Loan - Revolver Prime | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.44% | 8.44% | 8.44% | 8.44% | 8.44% | 8.44% | 8.44% | |||||||
| Maturity date | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | |||||||
| Principal/Shares | $ 817 | |||||||||||||
| Investments, amortized cost | 817 | |||||||||||||
| Investments at fair value | $ 817 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Batteries Plus Holding Corporation [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | |||||||
| Investment, Identifier [Axis]: Batteries Plus Holding Corporation First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Interest rate | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | |||||||
| Maturity date | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | Jun. 30, 2023 | |||||||
| Principal/Shares | $ 28,672 | |||||||||||||
| Investments, amortized cost | 28,671 | |||||||||||||
| Investments at fair value | $ 28,671 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Batteries Plus Holding Corporation [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Blackbrush Oil & Gas, L.P. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,198 | $ 1,123 | ||||||||||||
| Investments, amortized cost | $ 1 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BlackbrushOilGasLPMember | bcsf:BlackbrushOilGasLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Equity Securities [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Blackbrush Oil & Gas, L.P. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% |
| Interest rate | 9.11% | 8.00% | 9.11% | 9.11% | 9.11% | 9.11% | 9.11% | 9.11% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% |
| Maturity date | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 |
| Principal/Shares | $ 8,995 | $ 12,336 | ||||||||||||
| Investments, amortized cost | 8,993 | 12,336 | ||||||||||||
| Investments at fair value | $ 8,995 | $ 12,336 | ||||||||||||
| PIK | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) | (2.00%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BlackbrushOilGasLPMember | bcsf:BlackbrushOilGasLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Blackbrush Oil & Gas, L.P. Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 38,505 | $ 36,084 | ||||||||||||
| Investments, amortized cost | 11,777 | 10,104 | ||||||||||||
| Investments at fair value | $ 29,476 | $ 19,720 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BlackbrushOilGasLPMember | bcsf:BlackbrushOilGasLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] | Energy Oil And Gas Noncontrolled Affiliate Investments [Member] |
| Investment, Identifier [Axis]: Brook Bidco Facility B First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.09% | 6.09% | 6.09% | 6.09% | 6.09% | 6.09% | 6.09% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 684 | |||||||||||||
| Investments, amortized cost | £ | 935 | |||||||||||||
| Investments at fair value | £ | £ 926 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoFacilityBMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Brook Bidco First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | |||||||
| Interest rate | 8.06% | 8.06% | 8.06% | 8.06% | 8.06% | 8.06% | 8.06% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 707 | |||||||||||||
| Investments, amortized cost | $ 964 | |||||||||||||
| Investments at fair value | $ 789 | |||||||||||||
| PIK | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan - Revolver Gbp libor 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 5,385 | |||||||||||||
| Investments, amortized cost | £ | 7,047 | |||||||||||||
| Investments at fair value | £ | £ 7,287 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoILimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | |||||||
| Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan - Revolver Gbp libor 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 7,180 | |||||||||||||
| Investments, amortized cost | £ | 9,396 | |||||||||||||
| Investments at fair value | £ | £ 9,716 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoILimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | |||||||
| Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan, One | ||||||||||||||
| Investments | ||||||||||||||
| PIK | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan, Three | ||||||||||||||
| Investments | ||||||||||||||
| PIK | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan, Two | ||||||||||||||
| Investments | ||||||||||||||
| PIK | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Investment, Identifier [Axis]: Brook Bidco Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | £ | £ 5,675 | |||||||||||||
| Investments, amortized cost | $ 7,783 | |||||||||||||
| Investments at fair value | $ 7,028 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Brook Bidco Series A Preferred Units Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 5,675 | |||||||||||||
| Investments, amortized cost | 7,783 | |||||||||||||
| Investments at fair value | $ 7,908 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoSeriesAPreferredUnitsMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: CB Nike IntermediateCo Ltd First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Interest rate | 7.56% | 5.75% | 7.56% | 7.56% | 7.56% | 7.56% | 7.56% | 7.56% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 |
| Principal/Shares | $ 344 | $ 347 | ||||||||||||
| Investments, amortized cost | 341 | 342 | ||||||||||||
| Investments at fair value | $ 344 | $ 347 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | C B Nike Intermediate Co Ltd [Member] | C B Nike Intermediate Co Ltd [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: CB Nike IntermediateCo Ltd First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 |
| Principal/Shares | $ 44 | |||||||||||||
| Investments, amortized cost | 44 | |||||||||||||
| Investments at fair value | $ 44 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | C B Nike Intermediate Co Ltd [Member] | C B Nike Intermediate Co Ltd [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: CB Titan Holdings, Inc. Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,953 | $ 1,953 | ||||||||||||
| Investments, amortized cost | 1,953 | 1,953 | ||||||||||||
| Investments at fair value | $ 918 | $ 1,153 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:CBTitanHoldingsIncMember | bcsf:CBTitanHoldingsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Identifier [Axis]: CPS Group Holdings, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.25% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 9.42% | 6.25% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 |
| Principal/Shares | $ 44,790 | $ 54,843 | ||||||||||||
| Investments, amortized cost | 44,582 | 54,517 | ||||||||||||
| Investments at fair value | $ 44,790 | $ 54,843 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | C P S Group Holdings, Inc [Member] | C P S Group Holdings, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: CPS Group Holdings, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 | Mar. 03, 2025 |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | C P S Group Holdings, Inc [Member] | C P S Group Holdings, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Identifier [Axis]: CST Buyer Company First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.55% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% |
| Interest rate | 8.62% | 6.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 |
| Principal/Shares | $ 8,322 | $ 19,238 | ||||||||||||
| Investments, amortized cost | 8,294 | 19,122 | ||||||||||||
| Investments at fair value | $ 8,322 | $ 19,238 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | C S T Buyer Company [Member] | C S T Buyer Company [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: CST Buyer Company First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:JHCCHoldingsLLCMember | C S T Buyer Company [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Identifier [Axis]: Captain Ds LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | |||||||
| Principal/Shares | $ 2,326 | |||||||||||||
| Investments, amortized cost | 2,301 | |||||||||||||
| Investments at fair value | $ 2,326 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Captain D's LLC | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Captain D’s LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Captain D's LLC | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Identifier [Axis]: Captain D’s LLC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | Dec. 15, 2023 | |||||||
| Principal/Shares | $ 12,559 | |||||||||||||
| Investments, amortized cost | 12,539 | |||||||||||||
| Investments at fair value | $ 12,559 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Captain D's LLC | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Cardo First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 6.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 7.09% | 6.50% | 7.09% | 7.09% | 7.09% | 7.09% | 7.09% | 7.09% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 |
| Principal/Shares | $ 98 | $ 10,898 | ||||||||||||
| Investments, amortized cost | 97 | 10,795 | ||||||||||||
| Investments at fair value | $ 98 | $ 10,898 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:CardoMember | bcsf:CardoMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Caribou Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | |||||||
| Maturity date | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | |||||||
| Principal/Shares | £ | £ 8,070 | |||||||||||||
| Investments, amortized cost | $ 10,799 | |||||||||||||
| Investments at fair value | $ 9,014 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Caribou Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Caribou Bidco Limited First Lien Senior Secured Loan Not Qualifying | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | |||||||
| Maturity date | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | |||||||
| Principal/Shares | £ | £ 16 | |||||||||||||
| Investments, amortized cost | $ 20 | |||||||||||||
| Investments at fair value | $ 18 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Caribou Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Chamber Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 7.85% | 7.85% | 7.85% | 7.85% | 7.85% | 7.85% | 7.85% | |||||||
| Maturity date | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | |||||||
| Principal/Shares | $ 237 | |||||||||||||
| Investments, amortized cost | 235 | |||||||||||||
| Investments at fair value | $ 237 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ChamberBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Chamber Bidco Limited First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | |||||||
| Principal/Shares | $ 237 | |||||||||||||
| Investments, amortized cost | 234 | |||||||||||||
| Investments at fair value | $ 237 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ChamberBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Chase Industries, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 5.50% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.88% | 6.50% | 9.88% | 9.88% | 9.88% | 9.88% | 9.88% | 9.88% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 |
| Principal/Shares | $ 13,828 | $ 12,622 | ||||||||||||
| Investments, amortized cost | 13,801 | 12,586 | ||||||||||||
| Investments at fair value | $ 11,063 | $ 9,971 | ||||||||||||
| PIK | 7.00% | (1.50%) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | (1.50%) | (1.50%) | (1.50%) | (1.50%) | (1.50%) | (1.50%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ChaseIndustriesIncMember | bcsf:ChaseIndustriesIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Chase Industries, Inc.First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 5.50% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.88% | 6.50% | 9.88% | 9.88% | 9.88% | 9.88% | 9.88% | 9.88% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 | May 12, 2025 |
| Principal/Shares | $ 1,307 | $ 1,197 | ||||||||||||
| Investments, amortized cost | 1,306 | 1,195 | ||||||||||||
| Investments at fair value | $ 1,046 | $ 946 | ||||||||||||
| PIK | 7.00% | (1.50%) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | (1.50%) | (1.50%) | (1.50%) | (1.50%) | (1.50%) | (1.50%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ChaseIndustriesIncMember | bcsf:ChaseIndustriesIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: ClockSpring Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 10.05% | 10.05% | 10.05% | 10.05% | 10.05% | 10.05% | 10.05% | |||||||
| Maturity date | Aug. 01, 2025 | Aug. 01, 2025 | Aug. 01, 2025 | Aug. 01, 2025 | Aug. 01, 2025 | Aug. 01, 2025 | Aug. 01, 2025 | |||||||
| Principal/Shares | $ 5,235 | |||||||||||||
| Investments, amortized cost | 5,145 | |||||||||||||
| Investments at fair value | $ 5,131 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ClockSpringMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Concert Golf Partners Holdco First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | |||||||
| Principal/Shares | $ 6,847 | |||||||||||||
| Investments, amortized cost | 6,724 | |||||||||||||
| Investments at fair value | $ 6,778 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ConcertGolfPartnersHoldcoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Concert Golf Partners Holdco LLC First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | |||||||
| Maturity date | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | Mar. 30, 2029 | |||||||
| Principal/Shares | $ 1,065 | |||||||||||||
| Investments, amortized cost | 987 | |||||||||||||
| Investments at fair value | $ 1,023 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ConcertGolfPartnersHoldcoLlcMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Concert Golf Partners Holdco LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.46% | 9.46% | 9.46% | 9.46% | 9.46% | 9.46% | 9.46% | |||||||
| Maturity date | Mar. 31, 2028 | Mar. 31, 2028 | Mar. 31, 2028 | Mar. 31, 2028 | Mar. 31, 2028 | Mar. 31, 2028 | Mar. 31, 2028 | |||||||
| Principal/Shares | $ 356 | |||||||||||||
| Investments, amortized cost | 310 | |||||||||||||
| Investments at fair value | $ 331 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ConcertGolfPartnersHoldcoLlcMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Conterra Ultra Broadband Holdings, Inc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | |||||||
| Principal/Shares | $ 6,321 | |||||||||||||
| Investments, amortized cost | 6,300 | |||||||||||||
| Investments at fair value | $ 6,332 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ConterraUltraBroadbandHoldingsIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: DC Blox Inc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | |||||||
| Interest rate | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | |||||||
| Maturity date | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | |||||||
| Principal/Shares | $ 16,998 | |||||||||||||
| Investments, amortized cost | 16,738 | |||||||||||||
| Investments at fair value | $ 16,998 | |||||||||||||
| PIK | (6.00%) | (6.00%) | (6.00%) | (6.00%) | (6.00%) | (6.00%) | (6.00%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DCBloxIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: DC Blox Inc Warrants | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 177 | |||||||||||||
| Investments, amortized cost | $ 2 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DCBloxIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Identifier [Axis]: DC Blox Inc,Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,822 | |||||||||||||
| Investments, amortized cost | 3,851 | |||||||||||||
| Investments at fair value | $ 4,449 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DCBloxIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Identifier [Axis]: DC Blox Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 2.00% | 2.00% | 2.00% | 2.00% | 2.00% | 2.00% | 2.00% | |||||||
| Interest rate | 11.29% | 11.29% | 11.29% | 11.29% | 11.29% | 11.29% | 11.29% | |||||||
| Maturity date | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | Mar. 22, 2026 | |||||||
| Principal/Shares | $ 25,404 | |||||||||||||
| Investments, amortized cost | 25,185 | |||||||||||||
| Investments at fair value | $ 25,404 | |||||||||||||
| PIK | (6.00%) | (6.00%) | (6.00%) | (6.00%) | (6.00%) | (6.00%) | (6.00%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DCBloxIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: DC Blox Inc. Warrants | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 177 | |||||||||||||
| Investments, amortized cost | $ 2 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DCBloxIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Identifier [Axis]: Darcy Partners Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 359 | |||||||||||||
| Investments, amortized cost | 359 | |||||||||||||
| Investments at fair value | $ 367 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Darcy Partners [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Darcy Partners First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | |||||||
| Interest rate | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | |||||||
| Maturity date | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | |||||||
| Principal/Shares | $ 1,530 | |||||||||||||
| Investments, amortized cost | 1,515 | |||||||||||||
| Investments at fair value | $ 1,515 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Darcy Partners [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Darcy Partners First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | Jun. 01, 2028 | |||||||
| Investments at fair value | $ (3) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Darcy Partners [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Datix Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.00% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% |
| Interest rate | 4.57% | 4.25% | 4.57% | 4.57% | 4.57% | 4.57% | 4.57% | 4.57% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% |
| Maturity date | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 |
| Principal/Shares | $ 42 | $ 42 | ||||||||||||
| Investments, amortized cost | $ 32 | 32 | ||||||||||||
| Investments at fair value | $ 26 | $ 31 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DatixBidcoLimitedMember | bcsf:DatixBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember |
| Investment, Identifier [Axis]: Datix Bidco Limited First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | |||||||
| Interest rate | 4.96% | 4.96% | 4.96% | 4.96% | 4.96% | 4.96% | 4.96% | |||||||
| Maturity date | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | |||||||
| Principal/Shares | € | € 10 | |||||||||||||
| Investments, amortized cost | € | 13 | |||||||||||||
| Investments at fair value | € | € 13 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DatixBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Datix Bidco Limited Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% |
| Interest rate | 9.44% | 8.21% | 9.44% | 9.44% | 9.44% | 9.44% | 9.44% | 9.44% | 8.21% | 8.21% | 8.21% | 8.21% | 8.21% | 8.21% |
| Maturity date | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 |
| Principal/Shares | £ 121 | € 121 | ||||||||||||
| Investments, amortized cost | $ 164 | 164 | ||||||||||||
| Investments at fair value | $ 132 | € 164 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DatixBidcoLimitedMember | bcsf:DatixBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | London Interbank Offered Rate (LIBOR) [Member] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Direct Travel, Inc First Lien Senior Secured Loan - Delayed Draw 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 3,440 | |||||||||||||
| Investments, amortized cost | 3,440 | |||||||||||||
| Investments at fair value | $ 3,371 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc First Lien Senior Secured Loan - Delayed Draw 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 1,741 | |||||||||||||
| Investments, amortized cost | 1,741 | |||||||||||||
| Investments at fair value | $ 1,707 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc First Lien Senior Secured Loan - Delayed Draw 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 8.28% | 8.28% | 8.28% | 8.28% | 8.28% | 8.28% | 8.28% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 4,125 | |||||||||||||
| Investments, amortized cost | 4,125 | |||||||||||||
| Investments at fair value | $ 4,125 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 1.00% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% |
| Interest rate | 12.17% | 9.50% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% |
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 |
| Principal/Shares | $ 58,721 | $ 57,555 | ||||||||||||
| Investments, amortized cost | 58,721 | 57,555 | ||||||||||||
| Investments at fair value | $ 57,547 | $ 48,347 | ||||||||||||
| PIK | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | Direct Travel, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Direct Travel, Inc First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.00% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 10.17% | 7.00% | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 |
| Principal/Shares | $ 4,841 | $ 202 | ||||||||||||
| Investments, amortized cost | 4,841 | 202 | ||||||||||||
| Investments at fair value | $ 4,841 | $ 202 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | Direct Travel, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Direct Travel, Inc First Lien Senior Secured Loan 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 202 | |||||||||||||
| Investments, amortized cost | 202 | |||||||||||||
| Investments at fair value | $ 202 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 68 | $ 68 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | Direct Travel, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Equity Securities [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] |
| Investment, Identifier [Axis]: Direct Travel, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | |||||||
| Interest rate | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 4,766 | |||||||||||||
| Investments, amortized cost | 4,766 | |||||||||||||
| Investments at fair value | $ 4,766 | |||||||||||||
| PIK | (6.30%) | (6.30%) | (6.30%) | (6.30%) | (6.30%) | (6.30%) | (6.30%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | |||||||
| Interest rate | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 3,370 | |||||||||||||
| Investments, amortized cost | 3,370 | |||||||||||||
| Investments at fair value | $ 2,831 | |||||||||||||
| PIK | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc. First Lien Senior Secured Loan - Delayed Draw 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | 1.00% | |||||||
| Interest rate | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 1,710 | |||||||||||||
| Investments, amortized cost | 1,710 | |||||||||||||
| Investments at fair value | $ 1,436 | |||||||||||||
| PIK | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | (8.28%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Direct Travel, Inc. First Lien Senior Secured Loan - Delayed Draw 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Maturity date | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | Oct. 02, 2023 | |||||||
| Principal/Shares | $ 4,125 | |||||||||||||
| Investments, amortized cost | 4,125 | |||||||||||||
| Investments at fair value | $ 4,125 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Direct Travel, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | Transportation Consumer Non Controlled Affiliate [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Drilling Info Holdings, Inc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% |
| Interest rate | 7.37% | 4.35% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% | 4.35% |
| Maturity date | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 | Jul. 30, 2025 |
| Principal/Shares | $ 11,178 | $ 22,152 | ||||||||||||
| Investments, amortized cost | 11,160 | 22,101 | ||||||||||||
| Investments at fair value | $ 10,815 | $ 21,930 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DrillingInfoHoldingsIncMember | bcsf:DrillingInfoHoldingsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Eagle Rock Capital Corporation Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,345 | $ 2,354 | ||||||||||||
| Investments, amortized cost | 3,345 | 2,354 | ||||||||||||
| Investments at fair value | $ 3,798 | $ 2,354 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:EagleRockCapitalCorporationMember | bcsf:EagleRockCapitalCorporationMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: East BCC Coinvest II, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,419 | $ 1,419 | ||||||||||||
| Investments, amortized cost | 1,419 | 1,419 | ||||||||||||
| Investments at fair value | $ 989 | $ 1,065 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:EastBCCCoinvestIILLCMember | bcsf:EastBCCCoinvestIILLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] |
| Investment, Identifier [Axis]: Efficient Collaborative Retail Marketing Company, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | |||||||
| Maturity date | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | |||||||
| Principal/Shares | $ 1,275 | |||||||||||||
| Investments, amortized cost | 1,275 | |||||||||||||
| Investments at fair value | $ 1,275 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Efficient Collaborative Retail Marketing Company, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Efficient Collaborative Retail Marketing Company, LLC First Lien Senior Secured Loan - Revolver Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | |||||||
| Principal/Shares | $ 1,275 | |||||||||||||
| Investments, amortized cost | 1,275 | |||||||||||||
| Investments at fair value | $ 1,275 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Efficient Collaborative Retail Marketing Company, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Efficient Collaborative Retail Marketing Company, LLC First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Interest rate | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | |||||||
| Maturity date | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | |||||||
| Principal/Shares | $ 15,006 | |||||||||||||
| Investments, amortized cost | 15,006 | |||||||||||||
| Investments at fair value | $ 13,543 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Efficient Collaborative Retail Marketing Company, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Efficient Collaborative Retail Marketing Company, LLC First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Interest rate | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | |||||||
| Maturity date | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | Jun. 15, 2024 | |||||||
| Principal/Shares | $ 9,736 | |||||||||||||
| Investments, amortized cost | 9,764 | |||||||||||||
| Investments at fair value | $ 8,787 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Efficient Collaborative Retail Marketing Company, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Efficient Collaborative Retail Marketing Company, LLC First Lien Senior Secured Loan Libor 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Interest rate | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | |||||||
| Maturity date | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | |||||||
| Principal/Shares | $ 15,095 | |||||||||||||
| Investments, amortized cost | 15,114 | |||||||||||||
| Investments at fair value | $ 14,340 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Efficient Collaborative Retail Marketing Company, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Efficient Collaborative Retail Marketing Company, LLC First Lien Senior Secured Loan Libor 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Interest rate | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | |||||||
| Maturity date | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | Jun. 15, 2022 | |||||||
| Principal/Shares | $ 9,788 | |||||||||||||
| Investments, amortized cost | 9,800 | |||||||||||||
| Investments at fair value | $ 9,298 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Efficient Collaborative Retail Marketing Company, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Electronics For Imaging, Inc. Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | |||||||
| Interest rate | 9.10% | 9.10% | 9.10% | 9.10% | 9.10% | 9.10% | 9.10% | |||||||
| Maturity date | Jul. 23, 2027 | Jul. 23, 2027 | Jul. 23, 2027 | Jul. 23, 2027 | Jul. 23, 2027 | Jul. 23, 2027 | Jul. 23, 2027 | |||||||
| Principal/Shares | $ 12,070 | |||||||||||||
| Investments, amortized cost | 11,460 | |||||||||||||
| Investments at fair value | $ 11,285 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ElectronicsForImagingIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Element Buyer, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 8.62% | 6.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 |
| Principal/Shares | $ 36,721 | $ 37,007 | ||||||||||||
| Investments, amortized cost | 36,878 | 37,199 | ||||||||||||
| Investments at fair value | $ 36,721 | $ 37,007 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Element Buyer, Inc [Member] | Element Buyer, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Element Buyer, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 8.62% | 6.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jul. 19, 2025 | Jul. 18, 2025 | Jul. 19, 2025 | Jul. 19, 2025 | Jul. 19, 2025 | Jul. 19, 2025 | Jul. 19, 2025 | Jul. 19, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 | Jul. 18, 2025 |
| Principal/Shares | $ 10,993 | $ 11,078 | ||||||||||||
| Investments, amortized cost | 11,008 | 11,097 | ||||||||||||
| Investments at fair value | $ 10,993 | $ 11,078 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Element Buyer, Inc [Member] | Element Buyer, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Element Buyer, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 8.62% | 6.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 | Jul. 19, 2024 |
| Principal/Shares | $ 850 | $ 1,700 | ||||||||||||
| Investments, amortized cost | 831 | 1,672 | ||||||||||||
| Investments at fair value | $ 850 | $ 1,700 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Element Buyer, Inc [Member] | Element Buyer, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Elevator Holdco Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2 | $ 2 | ||||||||||||
| Investments, amortized cost | 2,448 | 2,448 | ||||||||||||
| Investments at fair value | $ 3,083 | $ 2,550 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ElevatorHoldcoIncMember | bcsf:ElevatorHoldcoIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Identifier [Axis]: Eleven Software First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | |||||||
| Interest rate | 11.55% | 11.55% | 11.55% | 11.55% | 11.55% | 11.55% | 11.55% | |||||||
| Maturity date | Apr. 25, 2027 | Apr. 25, 2027 | Apr. 25, 2027 | Apr. 25, 2027 | Apr. 25, 2027 | Apr. 25, 2027 | Apr. 25, 2027 | |||||||
| Principal/Shares | $ 7,439 | |||||||||||||
| Investments, amortized cost | 7,369 | |||||||||||||
| Investments at fair value | $ 7,365 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Eleven Software [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Eleven Software First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Sep. 25, 2026 | Sep. 25, 2026 | Sep. 25, 2026 | Sep. 25, 2026 | Sep. 25, 2026 | Sep. 25, 2026 | Sep. 25, 2026 | |||||||
| Investments at fair value | $ (15) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Eleven Software [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Eleven Software Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 896 | |||||||||||||
| Investments, amortized cost | 896 | |||||||||||||
| Investments at fair value | $ 896 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Eleven Software [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Elk Parent Holdings, LP Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | $ 1 | ||||||||||||
| Investments, amortized cost | 12 | 12 | ||||||||||||
| Investments at fair value | $ 487 | $ 407 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ElkParentHoldingsLPMember | bcsf:ElkParentHoldingsLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Identifier [Axis]: Elk Parent Holdings, LP Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 120 | $ 120 | ||||||||||||
| Investments, amortized cost | 1,202 | 1,202 | ||||||||||||
| Investments at fair value | $ 1,514 | $ 1,427 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ElkParentHoldingsLPMember | bcsf:ElkParentHoldingsLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Identifier [Axis]: Ergotron Acquisition Llc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.89% | 8.89% | 8.89% | 8.89% | 8.89% | 8.89% | 8.89% | |||||||
| Maturity date | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | Jul. 06, 2028 | |||||||
| Principal/Shares | $ 12,250 | |||||||||||||
| Investments, amortized cost | 12,010 | |||||||||||||
| Investments at fair value | $ 12,005 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ErgotronAcquisitionLlcMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: FCG Acquisitions, Inc. Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 4 | $ 4 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:FCGAcquisitionsIncMember | bcsf:FCGAcquisitionsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] |
| Investment, Identifier [Axis]: FL Hawk Intermediate Holdings, Inc. Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Interest rate | 12.42% | 10.00% | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Maturity date | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 | Aug. 22, 2028 |
| Principal/Shares | $ 15,125 | $ 21,125 | ||||||||||||
| Investments, amortized cost | 14,744 | 20,543 | ||||||||||||
| Investments at fair value | $ 15,125 | $ 21,125 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:FLHawkIntermediateHoldingsIncMember | bcsf:FLHawkIntermediateHoldingsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: FNZ UK Finco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 7.76% | 7.76% | 7.76% | 7.76% | 7.76% | 7.76% | 7.76% | |||||||
| Maturity date | Sep. 30, 2026 | Sep. 30, 2026 | Sep. 30, 2026 | Sep. 30, 2026 | Sep. 30, 2026 | Sep. 30, 2026 | Sep. 30, 2026 | |||||||
| Principal/Shares | $ 7,741 | |||||||||||||
| Investments, amortized cost | 5,276 | |||||||||||||
| Investments at fair value | $ 4,830 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:FnzUkFincoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Fineline Technologies, Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 939 | $ 939 | ||||||||||||
| Investments, amortized cost | 939 | 939 | ||||||||||||
| Investments at fair value | $ 1,201 | $ 1,241 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:FinelineTechnologiesIncMember | bcsf:FinelineTechnologiesIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Identifier [Axis]: Forming Machining Industries Holdings, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% |
| Interest rate | 7.37% | 4.47% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 7.37% | 4.47% | 4.47% | 4.47% | 4.47% | 4.47% | 4.47% |
| Maturity date | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 | Oct. 09, 2025 |
| Principal/Shares | $ 16,312 | $ 16,439 | ||||||||||||
| Investments, amortized cost | 16,242 | 16,352 | ||||||||||||
| Investments at fair value | $ 14,028 | $ 15,288 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:FormingMachiningIndustriesHoldingsLLCMember | bcsf:FormingMachiningIndustriesHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Forming Machining Industries Holdings, LLC Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% |
| Interest rate | 11.37% | 8.47% | 11.37% | 11.37% | 11.37% | 11.37% | 11.37% | 11.37% | 8.47% | 8.47% | 8.47% | 8.47% | 8.47% | 8.47% |
| Maturity date | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 | Oct. 09, 2026 |
| Principal/Shares | $ 6,540 | $ 6,540 | ||||||||||||
| Investments, amortized cost | 6,501 | 6,494 | ||||||||||||
| Investments at fair value | $ 5,297 | $ 5,821 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:FormingMachiningIndustriesHoldingsLLCMember | bcsf:FormingMachiningIndustriesHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: GSP Holdings LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.42% | 6.75% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Nov. 06, 2025 | Nov. 06, 2024 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2024 | Nov. 06, 2024 | Nov. 06, 2024 | Nov. 06, 2024 | Nov. 06, 2024 | Nov. 06, 2024 |
| Principal/Shares | $ 35,548 | $ 35,622 | ||||||||||||
| Investments, amortized cost | 35,523 | 35,516 | ||||||||||||
| Investments at fair value | $ 33,415 | $ 32,951 | ||||||||||||
| PIK | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GSPHoldingsLLCMember | bcsf:GSPHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: GSP Holdings LLC Senior First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 8.77% | 6.75% | 8.77% | 8.77% | 8.77% | 8.77% | 8.77% | 8.77% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 | Nov. 06, 2025 |
| Principal/Shares | $ 4,096 | $ 1,602 | ||||||||||||
| Investments, amortized cost | 4,073 | 1,573 | ||||||||||||
| Investments at fair value | $ 3,823 | $ 1,261 | ||||||||||||
| PIK | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) | (0.25%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GSPHoldingsLLCMember | bcsf:GSPHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Gale Aviation (Offshore) Co Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 90,450 | $ 88,985 | ||||||||||||
| Investments, amortized cost | 90,450 | 88,985 | ||||||||||||
| Investments at fair value | $ 88,695 | $ 72,839 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Gale Aviation Offshore Co [Member] | Gale Aviation Offshore Co [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Identifier [Axis]: Gluware First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | |||||||
| Interest rate | 12.50% | 12.50% | 12.50% | 12.50% | 12.50% | 12.50% | 12.50% | |||||||
| Maturity date | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | |||||||
| Principal/Shares | $ 19,404 | |||||||||||||
| Investments, amortized cost | 18,700 | |||||||||||||
| Investments at fair value | $ 18,434 | |||||||||||||
| PIK | (3.50%) | (3.50%) | (3.50%) | (3.50%) | (3.50%) | (3.50%) | (3.50%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GluwareMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Gluware T/L First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 12.50% | 12.50% | 12.50% | 12.50% | 12.50% | 12.50% | 12.50% | |||||||
| Interest rate | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | |||||||
| Maturity date | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | Oct. 15, 2025 | |||||||
| Principal/Shares | $ 18,898 | |||||||||||||
| Investments, amortized cost | 18,534 | |||||||||||||
| Investments at fair value | $ 18,520 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GluwareTLMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Gluware Warrant Warrants | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,328 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GluwareWarrantMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Gluware Warrants | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,328 | |||||||||||||
| Investments, amortized cost | 478 | |||||||||||||
| Investments at fair value | $ 435 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GluwareMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Goldman Sachs Financial Square Government Fund Institutional Share Class Cash Equivalents | ||||||||||||||
| Investments | ||||||||||||||
| Interest rate | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% | 0.03% |
| Principal/Shares | $ 31,249 | $ 177,554 | ||||||||||||
| Investments, amortized cost | 31,249 | 177,554 | ||||||||||||
| Investments at fair value | $ 31,249 | $ 177,554 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Cash Equivalents [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GoldmanSachsFinancialSquareGovernmentFundInstitutionalShareClassMember | bcsf:GoldmanSachsFinancialSquareGovernmentFundInstitutionalShareClassMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] | Cash Equivalents [Member] |
| Investment, Identifier [Axis]: Grammer Investment Holdings LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,011 | $ 1,011 | ||||||||||||
| Investments, amortized cost | 1,011 | 1,011 | ||||||||||||
| Investments at fair value | $ 1,011 | $ 1,056 | ||||||||||||
| PIK | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GrammerInvestmentHoldingsLLCMember | bcsf:GrammerInvestmentHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Identifier [Axis]: Grammer Investment Holdings LLC Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Principal/Shares | $ 9 | $ 8 | ||||||||||||
| Investments, amortized cost | 791 | 790 | ||||||||||||
| Investments at fair value | $ 894 | $ 830 | ||||||||||||
| PIK | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GrammerInvestmentHoldingsLLCMember | bcsf:GrammerInvestmentHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Identifier [Axis]: Grammer Investment Holdings LLC Warrants | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 122 | $ 122 | ||||||||||||
| Investments at fair value | $ 95 | $ 126 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GrammerInvestmentHoldingsLLCMember | bcsf:GrammerInvestmentHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] | Warrant [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Identifier [Axis]: Grammer Purchaser, Inc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | |||||||
| Interest rate | 7.57% | 7.57% | 7.57% | 7.57% | 7.57% | 7.57% | 7.57% | |||||||
| Maturity date | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | |||||||
| Principal/Shares | $ 3,843 | |||||||||||||
| Investments, amortized cost | 3,782 | |||||||||||||
| Investments at fair value | $ 3,834 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Grammer Purchaser, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Grammer Purchaser, Inc First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 |
| Principal/Shares | $ 7,319 | |||||||||||||
| Investments, amortized cost | 7,202 | |||||||||||||
| Investments at fair value | $ (2) | $ 7,319 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Grammer Purchaser, Inc [Member] | Grammer Purchaser, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Great Expressions Dental Center PC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | |||||||
| Principal/Shares | $ 7,831 | |||||||||||||
| Investments, amortized cost | 7,844 | |||||||||||||
| Investments at fair value | $ 7,205 | |||||||||||||
| PIK | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Great Expressions Dental Center P C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Great Expressions Dental Center PC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Sep. 28, 2022 | Sep. 28, 2022 | Sep. 28, 2022 | Sep. 28, 2022 | Sep. 28, 2022 | Sep. 28, 2022 | Sep. 28, 2022 | |||||||
| Principal/Shares | $ 1,027 | |||||||||||||
| Investments, amortized cost | 1,025 | |||||||||||||
| Investments at fair value | $ 929 | |||||||||||||
| PIK | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Great Expressions Dental Center P C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Great Expressions Dental Center PC First Lien Senior Secured Loan - Revolver Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Interest rate | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | |||||||
| Maturity date | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | |||||||
| Principal/Shares | $ 986 | |||||||||||||
| Investments, amortized cost | 983 | |||||||||||||
| Investments at fair value | $ 897 | |||||||||||||
| PIK | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Great Expressions Dental Center P C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Great Expressions Dental Center PC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Interest rate | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | 7.88% | |||||||
| Maturity date | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | Sep. 28, 2023 | |||||||
| Principal/Shares | $ 7,868 | |||||||||||||
| Investments, amortized cost | 7,899 | |||||||||||||
| Investments at fair value | $ 7,278 | |||||||||||||
| PIK | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Great Expressions Dental Center P C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Green Street Parent, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.75% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 8.62% | 5.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Maturity date | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 |
| Principal/Shares | $ 3,411 | $ 14,190 | ||||||||||||
| Investments, amortized cost | 3,369 | 13,988 | ||||||||||||
| Investments at fair value | $ 3,445 | $ 14,190 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Green Street Parent, L L C [Member] | Green Street Parent, L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Green Street Parent, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 | Aug. 27, 2025 |
| Investments at fair value | $ 24 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Green Street Parent, L L C [Member] | Green Street Parent, L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] |
| Investment, Identifier [Axis]: Green Street Parent, LLC First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.00% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% |
| Interest rate | 8.62% | 5.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Maturity date | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 | Aug. 27, 2026 |
| Principal/Shares | $ 4,466 | $ 4,500 | ||||||||||||
| Investments, amortized cost | 4,390 | 4,411 | ||||||||||||
| Investments at fair value | $ 4,511 | $ 4,500 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Green Street Parent, L L C [Member] | Green Street Parent, L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoan2Member | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member |
| Investment, Industry Sector [Extensible Enumeration] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] | Banking [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Horizon Telcom, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | |||||||
| Principal/Shares | $ 13,104 | |||||||||||||
| Investments, amortized cost | 13,045 | |||||||||||||
| Investments at fair value | $ 13,104 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:HorizonTelcomIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Horizon Telcom, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | |||||||
| Principal/Shares | $ 890 | |||||||||||||
| Investments, amortized cost | 888 | |||||||||||||
| Investments at fair value | $ 890 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:HorizonTelcomIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Horizon Telcom, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | Jun. 15, 2023 | |||||||
| Principal/Shares | $ 116 | |||||||||||||
| Investments, amortized cost | 114 | |||||||||||||
| Investments at fair value | $ 116 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:HorizonTelcomIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Insigneo Financial Group LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 2,140 | |||||||||||||
| Investments at fair value | $ 2,135 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:InsigneoFinancialGroupLlcMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | |||||||
| Investment, Identifier [Axis]: Insigneo Financial Group LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.19% | 9.19% | 9.19% | 9.19% | 9.19% | 9.19% | 9.19% | |||||||
| Maturity date | Aug. 01, 2028 | Aug. 01, 2028 | Aug. 01, 2028 | Aug. 01, 2028 | Aug. 01, 2028 | Aug. 01, 2028 | Aug. 01, 2028 | |||||||
| Principal/Shares | $ 3,825 | |||||||||||||
| Investments, amortized cost | 3,731 | |||||||||||||
| Investments at fair value | $ 3,729 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:InsigneoFinancialGroupLlcMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: International Entertainment Investments Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 6.47% | 6.47% | 6.47% | 6.47% | 6.47% | 6.47% | 6.47% | |||||||
| Maturity date | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | |||||||
| Principal/Shares | £ | £ 87 | |||||||||||||
| Investments, amortized cost | $ 107 | |||||||||||||
| Investments at fair value | $ 98 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:InternationalEntertainmentInvestmentsLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: International Entertainment Investments Limited First Lien Senior Secured Loan Gbp libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | |||||||
| Maturity date | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 | |||||||
| Principal/Shares | £ | £ 87 | |||||||||||||
| Investments, amortized cost | £ | 106 | |||||||||||||
| Investments at fair value | £ | £ 118 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:InternationalEntertainmentInvestmentsLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | |||||||
| Investment, Identifier [Axis]: International Senior Loan Program, LLC Equity Interest Investment Vehicles | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 57,774 | $ 41,823 | ||||||||||||
| Investments, amortized cost | 54,892 | 39,596 | ||||||||||||
| Investments at fair value | $ 54,584 | $ 44,444 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | International Senior Loan Program L L C [Member] | International Senior Loan Program L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] | Equity Interest Investment Vehicles [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: International Senior Loan Program, LLC Subordinated Note Investment Vehicles | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% |
| Interest rate | 10.29% | 9.00% | 10.29% | 10.29% | 10.29% | 10.29% | 10.29% | 10.29% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Maturity date | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 | Feb. 22, 2028 |
| Principal/Shares | $ 173,289 | $ 125,437 | ||||||||||||
| Investments, amortized cost | 173,289 | 125,437 | ||||||||||||
| Investments at fair value | $ 173,289 | $ 125,437 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | International Senior Loan Program L L C [Member] | International Senior Loan Program L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember | bcsf:SubordinatedNoteInvestmentVehiclesMember |
| Investment, Industry Sector [Extensible Enumeration] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] | Investment Vehicles [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Iris Holding, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 7.89% | 7.89% | 7.89% | 7.89% | 7.89% | 7.89% | 7.89% | |||||||
| Maturity date | Jun. 15, 2028 | Jun. 15, 2028 | Jun. 15, 2028 | Jun. 15, 2028 | Jun. 15, 2028 | Jun. 15, 2028 | Jun. 15, 2028 | |||||||
| Principal/Shares | $ 13,050 | |||||||||||||
| Investments, amortized cost | 12,388 | |||||||||||||
| Investments at fair value | $ 12,032 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:IrisHoldingInc.Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | Containers Packaging And Glass [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Island Medical Management Holdings, LLC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Maturity date | Sep. 01, 2023 | Sep. 01, 2023 | Sep. 01, 2023 | Sep. 01, 2023 | Sep. 01, 2023 | Sep. 01, 2023 | Sep. 01, 2023 | |||||||
| Principal/Shares | $ 8,520 | |||||||||||||
| Investments, amortized cost | 8,496 | |||||||||||||
| Investments at fair value | $ 8,371 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:IslandMedicalManagementHoldingsLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: JHCC Holdings, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.42% | 6.75% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 |
| Principal/Shares | $ 21,318 | $ 29,081 | ||||||||||||
| Investments, amortized cost | 21,148 | 28,799 | ||||||||||||
| Investments at fair value | $ 20,679 | $ 29,081 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:JHCCHoldingsLLCMember | bcsf:JHCCHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: JHCC Holdings, LLC First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 4.50% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% |
| Interest rate | 9.42% | 7.75% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% |
| Maturity date | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | |||||||
| Principal/Shares | $ 8,353 | $ 2,635 | ||||||||||||
| Investments, amortized cost | 8,328 | 2,618 | ||||||||||||
| Investments at fair value | $ 8,103 | $ 2,635 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:JHCCHoldingsLLCMember | bcsf:JHCCHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | us-gaap:PrimeRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember |
| Investment, Identifier [Axis]: JHCC Holdings, LLC First Lien Senior Secured Loan - Delayed Draw 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | |||||||
| Principal/Shares | $ 5,782 | |||||||||||||
| Investments, amortized cost | 5,776 | |||||||||||||
| Investments at fair value | $ 5,782 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:JHCCHoldingsLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: JHCC Holdings, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.42% | 6.75% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 | Sep. 09, 2025 |
| Principal/Shares | $ 1,620 | $ 894 | ||||||||||||
| Investments, amortized cost | 1,592 | 863 | ||||||||||||
| Investments at fair value | $ 1,535 | $ 894 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:JHCCHoldingsLLCMember | bcsf:JHCCHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | us-gaap:PrimeRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember |
| Investment, Identifier [Axis]: Jonathan Acquisition Company Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Interest rate | 12.60% | 10.00% | 12.60% | 12.60% | 12.60% | 12.60% | 12.60% | 12.60% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Maturity date | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 |
| Principal/Shares | $ 8,000 | $ 8,000 | ||||||||||||
| Investments, amortized cost | 7,836 | 7,821 | ||||||||||||
| Investments at fair value | $ 8,000 | $ 8,000 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:JonathanAcquisitionCompanyMember | bcsf:JonathanAcquisitionCompanyMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Kellstrom Aerospace Group, Inc Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | $ 1 | ||||||||||||
| Investments, amortized cost | 1,963 | 1,963 | ||||||||||||
| Investments at fair value | $ 792 | $ 913 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:KellstromAerospaceGroupIncMember | bcsf:KellstromAerospaceGroupIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Identifier [Axis]: Kellstrom Commercial Aerospace, Inc First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 5.50% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 11.25% | 6.50% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 |
| Principal/Shares | $ 2,666 | $ 2,239 | ||||||||||||
| Investments, amortized cost | 2,626 | 2,176 | ||||||||||||
| Investments at fair value | $ 2,410 | $ 1,919 | ||||||||||||
| PIK | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | (0.50%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Kellstrom Commercial Aerospace, Inc [Member] | Kellstrom Commercial Aerospace, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Kellstrom Commercial Aerospace, Inc First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 5.50% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 8.37% | 6.50% | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | 8.37% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 | Jul. 01, 2025 |
| Principal/Shares | $ 30,082 | $ 32,855 | ||||||||||||
| Investments, amortized cost | 29,772 | 32,430 | ||||||||||||
| Investments at fair value | $ 28,277 | $ 30,884 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Kellstrom Commercial Aerospace, Inc [Member] | Kellstrom Commercial Aerospace, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Learning Pool First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | |||||||
| Interest rate | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | € | € 279 | |||||||||||||
| Investments, amortized cost | $ 360 | |||||||||||||
| Investments at fair value | $ 312 | |||||||||||||
| PIK | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LearningPoolMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Learning Pool First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | |||||||
| Interest rate | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 100 | |||||||||||||
| Investments, amortized cost | $ 129 | |||||||||||||
| Investments at fair value | $ 111 | |||||||||||||
| PIK | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | (4.25%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LearningPoolMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Lightning Finco Limited First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | |||||||
| Principal/Shares | $ 1,300 | |||||||||||||
| Investments, amortized cost | 1,417 | |||||||||||||
| Investments at fair value | $ 1,274 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LightningFincoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Lightning Finco Limited First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.75% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 8.57% | 6.50% | 8.57% | 8.57% | 8.57% | 8.57% | 8.57% | 8.57% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Sep. 01, 2028 | Jul. 14, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 |
| Principal/Shares | $ 1,443 | $ 4,350 | ||||||||||||
| Investments, amortized cost | 1,408 | 4,234 | ||||||||||||
| Investments at fair value | $ 1,443 | $ 4,350 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LightningFincoLimitedMember | bcsf:LightningFincoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Lightning Finco Limited First Lien Senior Secured Loan Libor 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | |||||||
| Principal/Shares | $ 4,629 | |||||||||||||
| Investments, amortized cost | 4,506 | |||||||||||||
| Investments at fair value | $ 4,629 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LightningFincoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Lightning Holdings B, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 23,355 | $ 13,843 | ||||||||||||
| Investments, amortized cost | 23,665 | 14,152 | ||||||||||||
| Investments at fair value | $ 25,101 | $ 14,851 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] | Investment, Affiliated Issuer, Controlled [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LightningHoldingsBLLCMember | bcsf:LightningHoldingsBLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] | Transportation Cargo Controlled Affiliate [Member] |
| Investment, Identifier [Axis]: MRH Trowe Beteiligungsgesellschaft MBH First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | |||||||
| Principal/Shares | £ | £ 1,865 | |||||||||||||
| Investments, amortized cost | $ 1,858 | |||||||||||||
| Investments at fair value | $ 1,828 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Margaux U K Finance Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: MRHT Facility A First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | |||||||
| Principal/Shares | € | € 216 | |||||||||||||
| Investments, amortized cost | € | 248 | |||||||||||||
| Investments at fair value | € | € 245 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRHTFacilityAMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: MRHT First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 |
| Principal/Shares | € | € 500 | |||||||||||||
| Investments, amortized cost | $ 535 | |||||||||||||
| Investments at fair value | $ 485 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRHTMember | bcsf:MRHTAcquisitionFacilityMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: MRHT First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | |||||||
| Principal/Shares | € | € 216 | |||||||||||||
| Investments, amortized cost | $ 249 | |||||||||||||
| Investments at fair value | $ 209 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRHTMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: MRHT First Lien Senior Secured Loan 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | |||||||
| Principal/Shares | € | € 10,000 | |||||||||||||
| Investments, amortized cost | $ 10,125 | |||||||||||||
| Investments at fair value | $ 9,704 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRHTMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: MRI Software LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.17% | 6.50% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 |
| Principal/Shares | $ 25,728 | $ 25,926 | ||||||||||||
| Investments, amortized cost | 25,667 | 25,850 | ||||||||||||
| Investments at fair value | $ 25,004 | $ 25,926 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRISoftwareLLCMember | bcsf:MRISoftwareLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: MRI Software LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 | Feb. 10, 2026 |
| Investments, amortized cost | $ 52 | $ 48 | ||||||||||||
| Investments at fair value | $ (50) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRISoftwareLLCMember | bcsf:MRISoftwareLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: MZR Aggregator Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | $ 1 | ||||||||||||
| Investments, amortized cost | 798 | 798 | ||||||||||||
| Investments at fair value | $ 791 | $ 798 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MZRAggregatorMember | bcsf:MZRAggregatorMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Identifier [Axis]: MZR Buyer, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Interest rate | 10.42% | 7.75% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% |
| Maturity date | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 |
| Principal/Shares | $ 16,849 | $ 40,228 | ||||||||||||
| Investments, amortized cost | 16,651 | 39,551 | ||||||||||||
| Investments at fair value | $ 16,849 | $ 40,228 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MZRBuyerLLCMember | bcsf:MZRBuyerLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: MZR Buyer, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 | Dec. 21, 2026 |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MZRBuyerLLCMember | bcsf:MZRBuyerLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Mach Acquisition R/C Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Interest rate | 10.11% | 10.11% | 10.11% | 10.11% | 10.11% | 10.11% | 10.11% | |||||||
| Maturity date | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 |
| Principal/Shares | $ 3,013 | |||||||||||||
| Investments, amortized cost | 2,850 | |||||||||||||
| Investments at fair value | $ 2,410 | $ (201) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Mach Acquisition R C [Member] | Mach Acquisition R C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Mach Acquisition T/L First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Interest rate | 10.24% | 8.50% | 10.24% | 10.24% | 10.24% | 10.24% | 10.24% | 10.24% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Maturity date | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | Oct. 18, 2026 | |||||||
| Principal/Shares | $ 33,143 | $ 32,640 | ||||||||||||
| Investments, amortized cost | 32,602 | 32,006 | ||||||||||||
| Investments at fair value | $ 31,154 | $ 31,987 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MachAcquisitionTLMember | bcsf:MachAcquisitionTLMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Margaux Acquisition Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | |||||||
| Principal/Shares | $ 28,334 | |||||||||||||
| Investments, amortized cost | 28,000 | |||||||||||||
| Investments at fair value | $ 28,334 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Margaux Acquisition Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Margaux Acquisition Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | |||||||
| Principal/Shares | $ 9,198 | |||||||||||||
| Investments, amortized cost | 9,173 | |||||||||||||
| Investments at fair value | $ 9,198 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Margaux Acquisition Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Margaux Acquisition Inc. First Lien Senior Secured Loan - Delayed Draw Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.03% | 8.03% | 8.03% | 8.03% | 8.03% | 8.03% | 8.03% | |||||||
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | |||||||
| Principal/Shares | $ 9,128 | |||||||||||||
| Investments, amortized cost | 9,109 | |||||||||||||
| Investments at fair value | $ 9,083 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Margaux Acquisition Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Margaux Acquisition Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.03% | 8.03% | 8.03% | 8.03% | 8.03% | 8.03% | 8.03% | |||||||
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | |||||||
| Principal/Shares | $ 17,637 | |||||||||||||
| Investments, amortized cost | 17,472 | |||||||||||||
| Investments at fair value | $ 17,548 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Margaux Acquisition Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Margaux Acquisition, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 |
| Investments at fair value | $ (14) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Margaux Acquisition Inc [Member] | Margaux Acquisition Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance |
| Investment, Identifier [Axis]: Margaux UK Finance Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.50% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 7.06% | 6.50% | 7.06% | 7.06% | 7.06% | 7.06% | 7.06% | 7.06% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 |
| Principal/Shares | $ 7,512 | £ 7,551 | ||||||||||||
| Investments, amortized cost | 9,697 | 9,740 | ||||||||||||
| Investments at fair value | $ 8,307 | £ 10,218 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Margaux U K Finance Limited [Member] | Margaux U K Finance Limited [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember |
| Investment, Identifier [Axis]: Margaux UK Finance Limited First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 | Dec. 19, 2024 |
| Principal/Shares | £ | £ 89 | |||||||||||||
| Investments, amortized cost | £ | 112 | |||||||||||||
| Investments at fair value | $ (6) | £ 120 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Margaux U K Finance Limited [Member] | Margaux U K Finance Limited [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | |||||||
| Investment, Identifier [Axis]: Meriplex Communications, Ltd. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 7.95% | 7.95% | 7.95% | 7.95% | 7.95% | 7.95% | 7.95% | |||||||
| Maturity date | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | |||||||
| Principal/Shares | $ 15,294 | |||||||||||||
| Investments, amortized cost | 15,009 | |||||||||||||
| Investments at fair value | $ 14,988 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Meriplex Communications Ltd. [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Meriplex Communications, Ltd. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 7.95% | 7.95% | 7.95% | 7.95% | 7.95% | 7.95% | 7.95% | |||||||
| Maturity date | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | |||||||
| Principal/Shares | $ 2,353 | |||||||||||||
| Investments, amortized cost | 2,234 | |||||||||||||
| Investments at fair value | $ 2,231 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Meriplex Communications Ltd. [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Meriplex Communications, Ltd. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 8.18% | 8.18% | 8.18% | 8.18% | 8.18% | 8.18% | 8.18% | |||||||
| Maturity date | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | Jul. 17, 2028 | |||||||
| Principal/Shares | $ 188 | |||||||||||||
| Investments, amortized cost | 134 | |||||||||||||
| Investments at fair value | $ 132 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Meriplex Communications Ltd. [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | Telecommunications [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Mertus 522. GmbH First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Interest rate | 8.11% | 6.25% | 8.11% | 8.11% | 8.11% | 8.11% | 8.11% | 8.11% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 |
| Principal/Shares | € | € 131 | € 225 | ||||||||||||
| Investments, amortized cost | $ 142 | 247 | ||||||||||||
| Investments at fair value | $ 126 | € 255 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Mertus522GmbHMember | bcsf:Mertus522GmbHMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| Investment, Identifier [Axis]: Mertus 522. GmbH First Lien Senior Secured Loan - Delayed Draw Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | |||||||
| Principal/Shares | € | € 131 | |||||||||||||
| Investments, amortized cost | € | 142 | |||||||||||||
| Investments at fair value | € | € 149 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Mertus522GmbHMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Mertus 522. GmbH First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | |||||||
| Principal/Shares | € | € 225 | |||||||||||||
| Investments, amortized cost | $ 247 | |||||||||||||
| Investments at fair value | $ 216 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Mertus522GmbHMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Morrow Sodali First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | |||||||
| Investments at fair value | $ (40) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Morrow Sodali [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | |||||||
| Investment, Identifier [Axis]: Morrow Sodali First Lien Senior Secured Loan - Delayed Draw 2 | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | |||||||
| Investments at fair value | $ (34) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Morrow Sodali [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | |||||||
| Investment, Identifier [Axis]: Morrow Sodali First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 8.65% | 8.65% | 8.65% | 8.65% | 8.65% | 8.65% | 8.65% | |||||||
| Maturity date | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | Apr. 25, 2028 | |||||||
| Principal/Shares | $ 266 | |||||||||||||
| Investments, amortized cost | 236 | |||||||||||||
| Investments at fair value | $ 234 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Morrow Sodali [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | Banking Finance Insurance And Real Estate Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Music Creation Group Bidco GmbH First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | |||||||
| Maturity date | Aug. 03, 2027 | Aug. 03, 2027 | Aug. 03, 2027 | Aug. 03, 2027 | Aug. 03, 2027 | Aug. 03, 2027 | Aug. 03, 2027 | |||||||
| Principal/Shares | $ 4,065 | |||||||||||||
| Investments, amortized cost | 3,974 | |||||||||||||
| Investments at fair value | $ 4,014 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MusicCreationGroupBidcoGmbHMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: NPC International, Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 428 | $ 564 | ||||||||||||
| Investments, amortized cost | 639 | 843 | ||||||||||||
| Investments at fair value | $ 121 | $ 228 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:NPCInternationalIncMember | bcsf:NPCInternationalIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] | Beverage Foodand Tobacco Sector [Member] |
| Investment, Identifier [Axis]: New Era Cap Co., Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Maturity date | Sep. 10, 2023 | Sep. 10, 2023 | Sep. 10, 2023 | Sep. 10, 2023 | Sep. 10, 2023 | Sep. 10, 2023 | Sep. 10, 2023 | |||||||
| Principal/Shares | $ 9,970 | |||||||||||||
| Investments, amortized cost | 9,970 | |||||||||||||
| Investments at fair value | $ 9,970 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:NewEraCapCoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: New Look (Delaware) Corporation First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 9,677 | |||||||||||||
| Investments, amortized cost | 9,590 | |||||||||||||
| Investments at fair value | $ 9,580 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look (Delaware) Corporation [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: New Look (Delaware) Corporation First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 386 | |||||||||||||
| Investments, amortized cost | 376 | |||||||||||||
| Investments at fair value | $ 363 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look (Delaware) Corporation [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: New Look Vision Group First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.67% | 6.25% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 |
| Principal/Shares | $ 81 | $ 322 | ||||||||||||
| Investments, amortized cost | $ 64 | 310 | ||||||||||||
| Investments at fair value | $ 58 | $ 322 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | New Look Vision Group [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember |
| Investment, Identifier [Axis]: New Look Vision Group First Lien Senior Secured Loan - Delayed Draw Cdor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 2,380 | |||||||||||||
| Investments, amortized cost | 1,868 | |||||||||||||
| Investments at fair value | $ 1,883 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| Investment, Identifier [Axis]: New Look Vision Group First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | |||||||
| Principal/Shares | $ 1,419 | |||||||||||||
| Investments, amortized cost | $ 1,055 | |||||||||||||
| Investments at fair value | $ 1,009 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| Investment, Identifier [Axis]: New Look Vision Group First Lien Senior Secured Loan - Revolver Cdor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | May 26, 2026 | |||||||
| Principal/Shares | $ 313 | |||||||||||||
| Investments, amortized cost | 228 | |||||||||||||
| Investments at fair value | $ 248 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| Investment, Identifier [Axis]: New Look Vision Group First Lien Senior Secured Loan Cdor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 9,750 | |||||||||||||
| Investments, amortized cost | 9,653 | |||||||||||||
| Investments at fair value | $ 9,750 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| Investment, Identifier [Axis]: New Milani Group LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.50% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Interest rate | 9.67% | 7.50% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Maturity date | Jun. 06, 2024 | Jun. 06, 2024 | Jun. 06, 2024 | Jun. 06, 2024 | Jun. 06, 2024 | Jun. 06, 2024 | Jun. 06, 2024 | |||||||
| Principal/Shares | $ 21,531 | $ 16,752 | ||||||||||||
| Investments, amortized cost | 21,039 | 16,678 | ||||||||||||
| Investments at fair value | $ 21,100 | $ 16,250 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:NewMilaniGroupLLCMember | bcsf:NewMilaniGroupLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: OGH Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 8.53% | 8.53% | 8.53% | 8.53% | 8.53% | 8.53% | 8.53% | |||||||
| Maturity date | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | |||||||
| Principal/Shares | £ | £ 13,299 | |||||||||||||
| Investments, amortized cost | $ 15,685 | |||||||||||||
| Investments at fair value | $ 14,706 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | OGH Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: OGH Bidco Limited First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | |||||||
| Investments at fair value | $ (69) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | OGH Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | |||||||
| Investment, Identifier [Axis]: OGH Bidco Limited First Lien Senior Secured Loan - Delayed Draw SONIA | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | |||||||
| Maturity date | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | Jun. 29, 2029 | |||||||
| Principal/Shares | £ | £ 5,172 | |||||||||||||
| Investments, amortized cost | $ 5,893 | |||||||||||||
| Investments at fair value | $ 5,719 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | OGH Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | Media Publishing [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Omni Intermediate DD T/L First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | |||||||
| Principal/Shares | $ 776 | |||||||||||||
| Investments, amortized cost | 769 | |||||||||||||
| Investments at fair value | $ 768 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniIntermediateDDTL1Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Omni Intermediate DD T/L First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | |||||||
| Principal/Shares | $ 46 | |||||||||||||
| Investments, amortized cost | 37 | |||||||||||||
| Investments at fair value | $ 37 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniIntermediateDDTL2Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Omni Intermediate First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 8.69% | 8.69% | 8.69% | 8.69% | 8.69% | 8.69% | 8.69% | |||||||
| Maturity date | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | |||||||
| Principal/Shares | $ 814 | |||||||||||||
| Investments, amortized cost | 815 | |||||||||||||
| Investments at fair value | $ 807 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniIntermediateMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Omni Intermediate First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | |||||||
| Principal/Shares | $ 366 | |||||||||||||
| Investments, amortized cost | 359 | |||||||||||||
| Investments at fair value | $ 366 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniIntermediateMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Omni Intermediate First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Nov. 30, 2026 | Nov. 30, 2026 | Nov. 30, 2026 | Nov. 30, 2026 | Nov. 30, 2026 | Nov. 30, 2026 | Nov. 30, 2026 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniIntermediateMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Identifier [Axis]: Omni Intermediate Holdings Closing Date Term Loan First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | Nov. 23, 2026 | |||||||
| Principal/Shares | $ 7,306 | |||||||||||||
| Investments, amortized cost | 7,233 | |||||||||||||
| Investments at fair value | $ 7,233 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniIntermediateHoldingsClosingDateTermLoanMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Omni Intermediate R/C First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Nov. 23, 2025 | Nov. 23, 2025 | Nov. 23, 2025 | Nov. 23, 2025 | Nov. 23, 2025 | Nov. 23, 2025 | Nov. 23, 2025 | |||||||
| Principal/Shares | $ 183 | |||||||||||||
| Investments, amortized cost | 183 | |||||||||||||
| Investments at fair value | $ 176 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Omni Intermediate R C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Omni Logistics, LLC Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Interest rate | 12.69% | 10.00% | 12.69% | 12.69% | 12.69% | 12.69% | 12.69% | 12.69% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Maturity date | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 | Dec. 30, 2027 |
| Principal/Shares | $ 8,770 | $ 13,770 | ||||||||||||
| Investments, amortized cost | 8,668 | 13,527 | ||||||||||||
| Investments at fair value | $ 8,770 | $ 13,770 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:OmniLogisticsLLCMember | bcsf:OmniLogisticsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Opus 2 First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Opus2Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Opus 2 First Lien Senior Secured Loan Sonia | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | |||||||
| Maturity date | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | |||||||
| Principal/Shares | £ | £ 123 | |||||||||||||
| Investments, amortized cost | £ | 167 | |||||||||||||
| Investments at fair value | £ | £ 166 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Opus2Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Opus2 Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2,272 | $ 1,460 | ||||||||||||
| Investments, amortized cost | 2,900 | 1,769 | ||||||||||||
| Investments at fair value | $ 2,880 | $ 2,373 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Opus2Member | bcsf:Opus2Member | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Identifier [Axis]: Opus2 First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.28% | 5.28% | 5.28% | 5.28% | 5.28% | 5.28% | 5.28% | |||||||
| Interest rate | 5.97% | 5.97% | 5.97% | 5.97% | 5.97% | 5.97% | 5.97% | |||||||
| Maturity date | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | |||||||
| Principal/Shares | $ 123 | |||||||||||||
| Investments, amortized cost | 167 | |||||||||||||
| Investments at fair value | $ 137 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Opus2Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: PPX Class A Units Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 33 | |||||||||||||
| Investments at fair value | $ 163 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PPXClassAUnitsMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | |||||||
| Investment, Identifier [Axis]: PPX Class B Units Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 33 | |||||||||||||
| Investments, amortized cost | 5,000 | |||||||||||||
| Investments at fair value | $ 5,279 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PPXClassBUnitsMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | |||||||
| Investment, Identifier [Axis]: PPX Preferred Equity 1 | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 33 | |||||||||||||
| Investments at fair value | $ 163 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PPXMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | |||||||
| Investment, Identifier [Axis]: PPX Preferred Equity 2 | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 33 | |||||||||||||
| Investments, amortized cost | 5,000 | |||||||||||||
| Investments at fair value | $ 5,678 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PPXMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | Hospitality Holdings [Member] | |||||||
| Investment, Identifier [Axis]: Paisley Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.93% | 6.93% | 6.93% | 6.93% | 6.93% | 6.93% | 6.93% | |||||||
| Maturity date | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | |||||||
| Principal/Shares | € | € 3,676 | |||||||||||||
| Investments, amortized cost | $ 4,336 | |||||||||||||
| Investments at fair value | $ 4,106 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Paisley Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Paisley Bidco Limited First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | |||||||
| Investments at fair value | € | € (86) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Paisley Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Identifier [Axis]: Paisley Bidco Limited First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.19% | 6.19% | 6.19% | 6.19% | 6.19% | 6.19% | 6.19% | |||||||
| Maturity date | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | |||||||
| Principal/Shares | £ | £ 32 | |||||||||||||
| Investments, amortized cost | $ 36 | |||||||||||||
| Investments at fair value | $ 31 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Paisley Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Paisley Bidco Limited First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | Nov. 24, 2028 | |||||||
| Principal/Shares | £ | £ 3,210 | |||||||||||||
| Investments, amortized cost | £ | 3,583 | |||||||||||||
| Investments at fair value | £ | £ 3,614 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Paisley Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Parcel 2 Go Acquisition Facility First Lien Senior Secured Loan Sonia | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 5.92% | 5.92% | 5.92% | 5.92% | 5.92% | 5.92% | 5.92% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | £ | £ 3,863 | |||||||||||||
| Investments, amortized cost | £ | 4,982 | |||||||||||||
| Investments at fair value | £ | £ 5,183 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Parcel2 Go Acquisition Facility [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Parcel 2 Go Facility B First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 5.80% | 5.80% | 5.80% | 5.80% | 5.80% | 5.80% | 5.80% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | £ | £ 125 | |||||||||||||
| Investments, amortized cost | £ | 169 | |||||||||||||
| Investments at fair value | £ | £ 169 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Parcel2GoFacilityBMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Parcel 2 Go Shares Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2,881 | |||||||||||||
| Investments, amortized cost | 3,983 | |||||||||||||
| Investments at fair value | $ 3,899 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Parcel2GoSharesMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Parcel2Go Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | € | € 3,605 | |||||||||||||
| Investments, amortized cost | $ 4,237 | |||||||||||||
| Investments at fair value | $ 3,462 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Parcel2GoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Parcel2Go First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | $ 39 | |||||||||||||
| Investments, amortized cost | 50 | |||||||||||||
| Investments at fair value | $ 43 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Parcel2GoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Parcel2Go First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 7.94% | 7.94% | 7.94% | 7.94% | 7.94% | 7.94% | 7.94% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | £ | £ 125 | |||||||||||||
| Investments, amortized cost | $ 169 | |||||||||||||
| Investments at fair value | $ 140 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Parcel2GoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Parmenion First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.69% | 6.69% | 6.69% | 6.69% | 6.69% | 6.69% | 6.69% | |||||||
| Maturity date | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | |||||||
| Principal/Shares | £ | £ 328 | |||||||||||||
| Investments, amortized cost | $ 408 | |||||||||||||
| Investments at fair value | $ 366 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ParmenionMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: PetroChoice Holdings, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | |||||||
| Principal/Shares | $ 9,740 | |||||||||||||
| Investments, amortized cost | 9,721 | |||||||||||||
| Investments at fair value | $ 9,327 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PetroChoiceHoldingsIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: PetroChoice Holdings, Inc. First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Maturity date | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | Aug. 19, 2022 | |||||||
| Principal/Shares | $ 6,445 | |||||||||||||
| Investments, amortized cost | 6,412 | |||||||||||||
| Investments at fair value | $ 6,171 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PetroChoiceHoldingsIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | Wholesale | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Precision Ultimate Holdings, LLC Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,417 | $ 1,417 | ||||||||||||
| Investments, amortized cost | 1,417 | 1,417 | ||||||||||||
| Investments at fair value | $ 1,401 | $ 1,204 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PrecisionUltimateHoldingsLLCMember | bcsf:PrecisionUltimateHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Identifier [Axis]: Premier Imaging, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | |||||||
| Maturity date | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | |||||||
| Principal/Shares | $ 7,159 | |||||||||||||
| Investments, amortized cost | 7,074 | |||||||||||||
| Investments at fair value | $ 7,087 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Premier Imaging, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Premier Imaging, LLC First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | |||||||
| Maturity date | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | Jan. 02, 2025 | |||||||
| Principal/Shares | $ 1,941 | |||||||||||||
| Investments, amortized cost | 1,863 | |||||||||||||
| Investments at fair value | $ 1,873 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Premier Imaging, L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Quidditch Acquisition, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 9.52% | 9.52% | 9.52% | 9.52% | 9.52% | 9.52% | 9.52% | |||||||
| Maturity date | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | |||||||
| Principal/Shares | $ 9,104 | |||||||||||||
| Investments, amortized cost | 9,154 | |||||||||||||
| Investments at fair value | $ 9,058 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:QuidditchAcquisitionIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Quidditch Acquisition, Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | |||||||
| Maturity date | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | Mar. 21, 2025 | |||||||
| Principal/Shares | $ 18,636 | |||||||||||||
| Investments, amortized cost | 18,626 | |||||||||||||
| Investments at fair value | $ 18,392 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:QuidditchAcquisitionIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: REP Coinvest III- A Omni, LP Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,377 | $ 1,377 | ||||||||||||
| Investments, amortized cost | 1,377 | 1,377 | ||||||||||||
| Investments at fair value | $ 3,568 | $ 2,616 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:REPCoinvestIII-AOmniLPMember | bcsf:REPCoinvestIII-AOmniLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Equity Securities [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] | Transportation Cargo [Member] |
| Investment, Identifier [Axis]: Reconomy First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 8.44% | 8.44% | 8.44% | 8.44% | 8.44% | 8.44% | 8.44% | |||||||
| Maturity date | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | |||||||
| Principal/Shares | £ | £ 6,118 | |||||||||||||
| Investments, amortized cost | $ 7,431 | |||||||||||||
| Investments at fair value | $ 6,834 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Reconomy [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Reconomy First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | |||||||
| Maturity date | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | |||||||
| Principal/Shares | $ 2,467 | |||||||||||||
| Investments, amortized cost | 2,578 | |||||||||||||
| Investments at fair value | $ 2,418 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Reconomy [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Reconomy First Lien Senior Secured Loan 3 | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Reconomy [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Identifier [Axis]: Reconomy First Lien Senior Secured Loan 4 | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | Jun. 24, 2029 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Reconomy [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Identifier [Axis]: Refine Intermediate, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% |
| Interest rate | 8.17% | 5.50% | 8.17% | 8.17% | 8.17% | 8.17% | 8.17% | 8.17% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Maturity date | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 | Mar. 03, 2027 |
| Principal/Shares | $ 21,894 | £ 1,094 | ||||||||||||
| Investments, amortized cost | $ 1,154 | 21,467 | ||||||||||||
| Investments at fair value | $ 1,094 | $ 21,894 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Refine Intermediate, Inc [Member] | Refine Intermediate, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | London Interbank Offered Rate (LIBOR) [Member] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Refine Intermediate, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 | Sep. 03, 2026 |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Refine Intermediate, Inc [Member] | Refine Intermediate, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| Investment, Identifier [Axis]: Regan Development Holdings Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 6.50% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Interest rate | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Apr. 18, 2023 | Apr. 18, 2022 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 |
| Principal/Shares | $ 2,087 | € 2,087 | ||||||||||||
| Investments, amortized cost | $ 2,274 | 2,274 | ||||||||||||
| Investments at fair value | $ 1,979 | $ 2,326 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ReganDevelopmentHoldingsLimitedMember | bcsf:ReganDevelopmentHoldingsLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| Investment, Identifier [Axis]: Regan Development Holdings Limited First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 6.50% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Interest rate | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Apr. 18, 2023 | Apr. 18, 2022 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 |
| Principal/Shares | $ 677 | € 677 | ||||||||||||
| Investments, amortized cost | $ 768 | 768 | ||||||||||||
| Investments at fair value | $ 642 | $ 754 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ReganDevelopmentHoldingsLimitedMember | bcsf:ReganDevelopmentHoldingsLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoan2Member | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| Investment, Identifier [Axis]: Regan Development Holdings Limited First Lien Senior Secured Loan 3 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 6.50% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Interest rate | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Apr. 18, 2023 | Apr. 18, 2022 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2023 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 | Apr. 18, 2022 |
| Principal/Shares | $ 6,335 | € 6,335 | ||||||||||||
| Investments, amortized cost | $ 6,868 | 6,895 | ||||||||||||
| Investments at fair value | $ 5,977 | $ 7,041 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ReganDevelopmentHoldingsLimitedMember | bcsf:ReganDevelopmentHoldingsLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| Investment, Identifier [Axis]: Revalize, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | |||||||
| Maturity date | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 |
| Principal/Shares | $ 5,371 | |||||||||||||
| Investments, amortized cost | 5,325 | |||||||||||||
| Investments at fair value | $ 5,331 | $ (134) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Revalize, Inc [Member] | Revalize, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Revalize, Inc. First Lien Senior Secured Loan - Delayed Draw 2 | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | |||||||
| Investments at fair value | $ (98) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Revalize, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Revalize, Inc. First Lien Senior Secured Loan - Delayed Draw Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | |||||||
| Principal/Shares | $ 5,130 | |||||||||||||
| Investments, amortized cost | 5,079 | |||||||||||||
| Investments at fair value | $ 5,079 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Revalize, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Revalize, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | |||||||
| Maturity date | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 | Apr. 15, 2027 |
| Principal/Shares | $ 1,340 | |||||||||||||
| Investments, amortized cost | 1,329 | |||||||||||||
| Investments at fair value | $ 1,330 | $ (13) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Revalize, Inc [Member] | Revalize, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: RoC Opco LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 11.49% | 11.49% | 11.49% | 11.49% | 11.49% | 11.49% | 11.49% | |||||||
| Maturity date | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 |
| Principal/Shares | $ 7,510 | |||||||||||||
| Investments, amortized cost | 7,423 | |||||||||||||
| Investments at fair value | $ 7,485 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RoCOpcoLLCMember | bcsf:RoCOpcoLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: RoC Opco LLCFirst Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Interest rate | 12.17% | 9.50% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% |
| Maturity date | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 |
| Principal/Shares | $ 15,080 | $ 40,079 | ||||||||||||
| Investments, amortized cost | 14,907 | 39,486 | ||||||||||||
| Investments at fair value | $ 15,042 | $ 40,079 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RoCOpcoLLCMember | bcsf:RoCOpcoLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Robinson Helicopter Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,592 | |||||||||||||
| Investments, amortized cost | 1,592 | |||||||||||||
| Investments at fair value | $ 1,592 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RobinsonHelicopterMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Identifier [Axis]: Robinson Helicopter First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 9.63% | 9.63% | 9.63% | 9.63% | 9.63% | 9.63% | 9.63% | |||||||
| Maturity date | Jun. 30, 2028 | Jun. 30, 2028 | Jun. 30, 2028 | Jun. 30, 2028 | Jun. 30, 2028 | Jun. 30, 2028 | Jun. 30, 2028 | |||||||
| Principal/Shares | $ 36,937 | |||||||||||||
| Investments, amortized cost | 36,129 | |||||||||||||
| Investments at fair value | $ 36,199 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RobinsonHelicopterMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: SAM First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | |||||||
| Interest rate | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | |||||||
| Maturity date | May 09, 2028 | May 09, 2028 | May 09, 2028 | May 09, 2028 | May 09, 2028 | May 09, 2028 | May 09, 2028 | |||||||
| Principal/Shares | $ 32,500 | |||||||||||||
| Investments, amortized cost | 32,213 | |||||||||||||
| Investments at fair value | $ 32,175 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SAMMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | |||||||
| Investment, Identifier [Axis]: Saltoun First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | |||||||
| Interest rate | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | |||||||
| Maturity date | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | |||||||
| Principal/Shares | $ 4,726 | |||||||||||||
| Investments, amortized cost | 4,726 | |||||||||||||
| Investments at fair value | $ 4,584 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Saltoun [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Identifier [Axis]: Saltoun First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | |||||||
| Interest rate | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | 10.50% | |||||||
| Maturity date | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | Apr. 11, 2028 | |||||||
| Principal/Shares | $ 1,352 | |||||||||||||
| Investments, amortized cost | 1,352 | |||||||||||||
| Investments at fair value | $ 881 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Saltoun [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | Hotel, Gaming & Leisure | |||||||
| Investment, Identifier [Axis]: Saturn Purchaser Corp. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.60% | 5.60% | 5.60% | 5.60% | 5.60% | 5.60% | 5.60% | |||||||
| Interest rate | 8.54% | 8.54% | 8.54% | 8.54% | 8.54% | 8.54% | 8.54% | |||||||
| Maturity date | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | |||||||
| Principal/Shares | $ 56,867 | |||||||||||||
| Investments, amortized cost | 56,303 | |||||||||||||
| Investments at fair value | $ 56,299 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Saturn Purchaser Corp [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Saturn Purchaser Corp. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.60% | 5.60% | 5.60% | 5.60% | 5.60% | 5.60% | 5.60% | |||||||
| Interest rate | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | |||||||
| Maturity date | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | Jul. 22, 2029 | |||||||
| Principal/Shares | $ 651 | |||||||||||||
| Investments, amortized cost | 604 | |||||||||||||
| Investments at fair value | $ 602 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Saturn Purchaser Corp [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Service Master Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 350 | |||||||||||||
| Investments, amortized cost | 350 | $ 327 | ||||||||||||
| Investments at fair value | $ 397 | $ 353 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ServiceMasterMember | bcsf:ServiceMasterMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Identifier [Axis]: Service Master First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Interest rate | 10.42% | 8.50% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Maturity date | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 |
| Principal/Shares | $ 929 | $ 939 | ||||||||||||
| Investments, amortized cost | 914 | 921 | ||||||||||||
| Investments at fair value | $ 929 | $ 939 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ServiceMasterMember | bcsf:ServiceMasterMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Service Master First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Interest rate | 11.10% | 8.50% | 11.10% | 11.10% | 11.10% | 11.10% | 11.10% | 11.10% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Maturity date | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 |
| Principal/Shares | $ 2,430 | $ 1,260 | ||||||||||||
| Investments, amortized cost | 2,357 | 1,176 | ||||||||||||
| Investments at fair value | $ 2,430 | $ 1,260 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ServiceMasterMember | bcsf:ServiceMasterMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Service Master First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 11.53% | 11.53% | 11.53% | 11.53% | 11.53% | 11.53% | 11.53% | |||||||
| Maturity date | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | Aug. 16, 2027 | |||||||
| Principal/Shares | $ 22,000 | |||||||||||||
| Investments, amortized cost | 22,000 | |||||||||||||
| Investments at fair value | $ 22,000 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ServiceMasterMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Smartronix First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | |||||||
| Maturity date | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | |||||||
| Principal/Shares | $ 12,668 | |||||||||||||
| Investments, amortized cost | 12,441 | |||||||||||||
| Investments at fair value | $ 12,351 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SmartronixMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Smartronix First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | |||||||
| Investments at fair value | $ (158) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SmartronixMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Smartronix RC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | |||||||
| Investments at fair value | $ (126) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SmartronixRCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Smartronix T/L First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Maturity date | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | Nov. 23, 2028 | |||||||
| Principal/Shares | $ 36,991 | |||||||||||||
| Investments, amortized cost | 36,260 | |||||||||||||
| Investments at fair value | $ 36,251 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SmartronixTLMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Solaray, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.50% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.40% | 6.50% | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 | Sep. 11, 2023 |
| Principal/Shares | $ 30,762 | $ 41,729 | ||||||||||||
| Investments, amortized cost | 30,762 | 41,729 | ||||||||||||
| Investments at fair value | $ 30,608 | $ 41,729 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Solaray L L C [Member] | Solaray L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Solaray, LLC First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.50% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.40% | 6.50% | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | 9.40% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 |
| Principal/Shares | $ 14,202 | $ 14,276 | ||||||||||||
| Investments, amortized cost | 14,202 | 14,276 | ||||||||||||
| Investments at fair value | $ 14,131 | $ 14,276 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Solaray L L C [Member] | Solaray L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Solaray, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.55% | 4.50% | 3.55% | 3.55% | 3.55% | 3.55% | 3.55% | 3.55% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% |
| Interest rate | 8.16% | 5.50% | 8.16% | 8.16% | 8.16% | 8.16% | 8.16% | 8.16% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Maturity date | Sep. 09, 2023 | Sep. 09, 2022 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2023 | Sep. 09, 2022 | Sep. 09, 2022 | Sep. 09, 2022 | Sep. 09, 2022 | Sep. 09, 2022 | Sep. 09, 2022 |
| Principal/Shares | $ 5,950 | $ 907 | ||||||||||||
| Investments, amortized cost | 5,950 | 895 | ||||||||||||
| Investments at fair value | $ 5,950 | $ 907 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Solaray L L C [Member] | Solaray L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Spring Finco BV, First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 8.07% | 8.07% | 8.07% | 8.07% | 8.07% | 8.07% | 8.07% | |||||||
| Maturity date | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | |||||||
| Principal/Shares | $ 49,343 | |||||||||||||
| Investments, amortized cost | 5,160 | |||||||||||||
| Investments at fair value | $ 4,646 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Spring Finco BV [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Spring Finco BV, First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | Jul. 15, 2029 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Spring Finco BV [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: Stanton Carpet Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Interest rate | 12.75% | 10.00% | 12.75% | 12.75% | 12.75% | 12.75% | 12.75% | 12.75% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Principal/Shares | $ 11,434 | $ 19,664 | ||||||||||||
| Investments, amortized cost | 11,229 | 19,277 | ||||||||||||
| Investments at fair value | $ 11,434 | $ 19,271 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:StantonCarpetMember | bcsf:StantonCarpetMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: SumUp Holdings Luxembourg S.a.r.l. First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Maturity date | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 |
| Principal/Shares | € | € 6,650 | € 6,650 | ||||||||||||
| Investments, amortized cost | $ 7,945 | 7,939 | ||||||||||||
| Investments at fair value | $ 6,519 | € 7,561 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SumUpHoldingsLuxembourgSarlMember | bcsf:SumUpHoldingsLuxembourgSarlMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| Investment, Identifier [Axis]: SumUp Holdings Luxembourg S.a.r.l. First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% |
| Maturity date | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 |
| Principal/Shares | € 155 | £ 10,055 | ||||||||||||
| Investments, amortized cost | $ 180 | 11,700 | ||||||||||||
| Investments at fair value | $ 152 | £ 11,432 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SumUpHoldingsLuxembourgSarlMember | bcsf:SumUpHoldingsLuxembourgSarlMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | London Interbank Offered Rate (LIBOR) [Member] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: SunMed Group Holdings, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 8.82% | 6.50% | 8.82% | 8.82% | 8.82% | 8.82% | 8.82% | 8.82% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jun. 16, 2027 | Jun. 16, 2028 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 |
| Principal/Shares | $ 590 | $ 18,510 | ||||||||||||
| Investments, amortized cost | 573 | 18,204 | ||||||||||||
| Investments at fair value | $ 550 | $ 18,510 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SunMedGroupHoldingsLLCMember | bcsf:SunMedGroupHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: SunMed Group Holdings, LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.42% | 6.50% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 9.42% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jun. 16, 2028 | Jun. 16, 2027 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2028 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 | Jun. 16, 2027 |
| Principal/Shares | $ 8,716 | $ 197 | ||||||||||||
| Investments, amortized cost | 8,585 | 177 | ||||||||||||
| Investments at fair value | $ 8,433 | $ 197 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SunMedGroupHoldingsLLCMember | bcsf:SunMedGroupHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Superna Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,463 | |||||||||||||
| Investments, amortized cost | 1,463 | |||||||||||||
| Investments at fair value | $ 1,514 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Superna Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Superna Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Interest rate | 9.52% | 9.52% | 9.52% | 9.52% | 9.52% | 9.52% | 9.52% | |||||||
| Maturity date | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | |||||||
| Principal/Shares | $ 14,958 | |||||||||||||
| Investments, amortized cost | 14,675 | |||||||||||||
| Investments at fair value | $ 14,808 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Superna Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Superna Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | |||||||
| Investments at fair value | $ (26) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Superna Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Superna Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | Mar. 06, 2028 | |||||||
| Investments at fair value | $ (26) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Superna Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Surrey Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 7.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Interest rate | 7.97% | 7.50% | 7.97% | 7.97% | 7.97% | 7.97% | 7.97% | 7.97% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Maturity date | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 |
| Principal/Shares | £ | £ 54 | £ 50 | ||||||||||||
| Investments, amortized cost | $ 67 | 62 | ||||||||||||
| Investments at fair value | $ 52 | £ 60 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SurreyBidcoLimitedMember | bcsf:SurreyBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember | bcsf:BritishPoundSterlingLondonInterbankOfferedRateLiborMember |
| Investment, Identifier [Axis]: Swoogo LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 |
| Investments at fair value | $ (22) | $ (25) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Swoogo L L C [Member] | Swoogo L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: Swoogo LLC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% |
| Interest rate | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% |
| Maturity date | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 | Dec. 09, 2026 |
| Principal/Shares | $ 2,330 | $ 2,330 | ||||||||||||
| Investments, amortized cost | 2,290 | 2,284 | ||||||||||||
| Investments at fair value | $ 2,289 | $ 2,283 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Swoogo L L C [Member] | Swoogo L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: TA/Weg Holdings First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 5.75% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 7.67% | 6.75% | 7.67% | 7.67% | 7.67% | 7.67% | 7.67% | 7.67% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Oct. 02, 2025 | Oct. 02, 2027 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 |
| Principal/Shares | $ 2,379 | $ 9,495 | ||||||||||||
| Investments, amortized cost | 2,369 | 9,495 | ||||||||||||
| Investments at fair value | $ 2,379 | $ 9,495 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TAWegHoldingsMember | bcsf:TAWegHoldingsMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: TA/Weg Holdings First Lien Senior Secured Loan - Delayed Draw 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 5.75% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 9.41% | 6.75% | 9.41% | 9.41% | 9.41% | 9.41% | 9.41% | 9.41% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Maturity date | Oct. 02, 2025 | Oct. 02, 2027 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2025 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 | Oct. 02, 2027 |
| Principal/Shares | $ 9,423 | $ 2,392 | ||||||||||||
| Investments, amortized cost | 9,423 | 2,381 | ||||||||||||
| Investments at fair value | $ 9,423 | $ 2,392 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TAWegHoldingsMember | bcsf:TAWegHoldingsMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: TCFIII Owl Finance, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | |||||||
| Interest rate | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | 12.00% | |||||||
| Maturity date | Jan. 30, 2027 | Jan. 30, 2027 | Jan. 30, 2027 | Jan. 30, 2027 | Jan. 30, 2027 | Jan. 30, 2027 | Jan. 30, 2027 | |||||||
| Principal/Shares | $ 4,697 | |||||||||||||
| Investments, amortized cost | 4,636 | |||||||||||||
| Investments at fair value | $ 4,603 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TCFIIIOwlFinanceLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | |||||||
| Investment, Identifier [Axis]: TEI Holdings Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 7.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Interest rate | 8.87% | 8.25% | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | 8.87% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% |
| Maturity date | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 | Dec. 23, 2026 |
| Principal/Shares | $ 38,475 | $ 48,720 | ||||||||||||
| Investments, amortized cost | 38,283 | 48,350 | ||||||||||||
| Investments at fair value | $ 38,475 | $ 48,720 | ||||||||||||
| PIK | (1.25%) | (1.25%) | (1.25%) | (1.25%) | (1.25%) | (1.25%) | (1.25%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | T E I Holdings Inc [Member] | T E I Holdings Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: TEI Holdings Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Maturity date | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 | Dec. 23, 2025 |
| Principal/Shares | $ 458 | |||||||||||||
| Investments, amortized cost | 412 | |||||||||||||
| Investments at fair value | $ 5 | $ 458 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | T E I Holdings Inc [Member] | T E I Holdings Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: TGI Sport Bidco Pty Ltd First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Apr. 30, 2027 | Apr. 30, 2027 | Apr. 30, 2027 | Apr. 30, 2027 | Apr. 30, 2027 | Apr. 30, 2027 | Apr. 30, 2027 | |||||||
| Investments at fair value | $ (151) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | T G I Sport Bidco Pty Ltd [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Identifier [Axis]: TGI Sport Bidco Pty Ltd First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 10.60% | 10.60% | 10.60% | 10.60% | 10.60% | 10.60% | 10.60% | |||||||
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | |||||||
| Principal/Shares | $ 4,166 | |||||||||||||
| Investments, amortized cost | $ 2,720 | |||||||||||||
| Investments at fair value | $ 2,520 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | T G I Sport Bidco Pty Ltd [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: TGI Sport Bidco Pty Ltd First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | |||||||
| Principal/Shares | $ 97 | |||||||||||||
| Investments, amortized cost | $ 75 | |||||||||||||
| Investments at fair value | $ 59 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | T G I Sport Bidco Pty Ltd [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | |||||||
| Investment, Identifier [Axis]: TGI Sport Bidco Pty Ltd First Lien Senior Secured Loan Bbsw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | |||||||
| Principal/Shares | $ 97 | |||||||||||||
| Investments, amortized cost | 75 | |||||||||||||
| Investments at fair value | $ 67 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | T G I Sport Bidco Pty Ltd [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | |||||||
| Investment, Identifier [Axis]: TLC Holdco LP Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1,281 | $ 1,188 | ||||||||||||
| Investments, amortized cost | $ 1,221 | 1,186 | ||||||||||||
| Investments at fair value | $ 431 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TLCHoldcoLPMember | bcsf:TLCHoldcoLPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] |
| Investment, Identifier [Axis]: TLC Purchaser, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | |||||||
| Investments at fair value | $ (1,409) | $ (854) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | T L C Purchaser, Inc [Member] | T L C Purchaser, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] |
| Investment, Identifier [Axis]: TLC Purchaser, Inc.First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Interest rate | 11.54% | 7.25% | 11.54% | 11.54% | 11.54% | 11.54% | 11.54% | 11.54% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% |
| Maturity date | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | |||||||
| Principal/Shares | $ 35,240 | $ 41,066 | ||||||||||||
| Investments, amortized cost | 34,579 | 40,511 | ||||||||||||
| Investments at fair value | $ 28,720 | $ 36,137 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | T L C Purchaser, Inc [Member] | T L C Purchaser, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: TLC Purchaser, Inc.First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 5.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 9.37% | 8.50% | 9.37% | 9.37% | 9.37% | 9.37% | 9.37% | 9.37% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Maturity date | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | Oct. 13, 2025 | |||||||
| Principal/Shares | $ 7,693 | $ 6,408 | ||||||||||||
| Investments, amortized cost | 7,536 | 6,296 | ||||||||||||
| Investments at fair value | $ 5,932 | $ 5,340 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | T L C Purchaser, Inc [Member] | T L C Purchaser, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Tangent Technologies Acquisition, LLCSecond Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.75% | 8.75% | 8.75% | 8.75% | 8.75% | 8.75% | 8.75% | |||||||
| Interest rate | 9.99% | 9.99% | 9.99% | 9.99% | 9.99% | 9.99% | 9.99% | |||||||
| Principal/Shares | $ 8,915 | |||||||||||||
| Investments, amortized cost | 8,752 | |||||||||||||
| Investments at fair value | $ 8,915 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TangentTechnologiesAcquisitionLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: TecoStar Holdings, Inc. Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% |
| Interest rate | 11.31% | 9.50% | 11.31% | 11.31% | 11.31% | 11.31% | 11.31% | 11.31% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% |
| Maturity date | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 | Nov. 01, 2024 |
| Principal/Shares | $ 9,472 | $ 9,472 | ||||||||||||
| Investments, amortized cost | 9,381 | 9,354 | ||||||||||||
| Investments at fair value | $ 9,022 | $ 8,951 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TecoStarHoldingsIncMember | bcsf:TecoStarHoldingsIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Thrasio, LLC First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 11.17% | 11.17% | 11.17% | 11.17% | 11.17% | 11.17% | 11.17% | |||||||
| Maturity date | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | |||||||
| Principal/Shares | $ 8,506 | |||||||||||||
| Investments, amortized cost | 8,320 | |||||||||||||
| Investments at fair value | $ 7,826 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Thrasio, LLC First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | |||||||
| Interest rate | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | 8.00% | |||||||
| Maturity date | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | Dec. 18, 2026 | |||||||
| Principal/Shares | $ 21,746 | |||||||||||||
| Investments, amortized cost | 21,241 | |||||||||||||
| Investments at fair value | $ 21,746 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ThrasioLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Tidel Engineering, L.P. First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | |||||||
| Principal/Shares | $ 38,155 | |||||||||||||
| Investments, amortized cost | 38,155 | |||||||||||||
| Investments at fair value | $ 38,155 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TidelEngineeringLPMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Tidel Engineering, L.P. First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | Mar. 01, 2024 | |||||||
| Principal/Shares | $ 6,337 | |||||||||||||
| Investments, amortized cost | 6,274 | |||||||||||||
| Investments at fair value | $ 6,336 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:TidelEngineeringLPMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | bcsf:FirstLienSeniorSecuredLoan2Member | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | Capital Equipment Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Titan Cloud Software, Inc First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | |||||||
| Interest rate | 9.63% | 9.63% | 9.63% | 9.63% | 9.63% | 9.63% | 9.63% | |||||||
| Maturity date | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | |||||||
| Principal/Shares | € | € 25,714 | |||||||||||||
| Investments, amortized cost | $ 25,457 | |||||||||||||
| Investments at fair value | $ 25,457 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Titan Cloud Software, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Titan Cloud Software, Inc First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | Sep. 07, 2029 | |||||||
| Investments at fair value | $ (114) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Titan Cloud Software, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Identifier [Axis]: Titan Cloud Software, Inc First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Sep. 07, 2028 | Sep. 07, 2028 | Sep. 07, 2028 | Sep. 07, 2028 | Sep. 07, 2028 | Sep. 07, 2028 | Sep. 07, 2028 | |||||||
| Investments at fair value | $ (57) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Titan Cloud Software, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | Environmental Industries Sector [Member] | |||||||
| Investment, Identifier [Axis]: Toro Private Investments II, LP Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 3,090 | $ 3,090 | ||||||||||||
| Investments, amortized cost | 3,090 | 3,090 | ||||||||||||
| Investments at fair value | $ 1,173 | $ 1,353 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ToroPrivateInvestmentsIILPMember | bcsf:ToroPrivateInvestmentsIILPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Equity Securities [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] | Equity Securities [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Toro Private Investments II, LP First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 6.75% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% |
| Interest rate | 10.42% | 6.90% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 10.42% | 6.90% | 6.90% | 6.90% | 6.90% | 6.90% | 6.90% |
| Maturity date | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 | May 29, 2026 |
| Principal/Shares | $ 6,744 | $ 6,706 | ||||||||||||
| Investments, amortized cost | 5,182 | 4,846 | ||||||||||||
| Investments at fair value | $ 4,794 | $ 5,603 | ||||||||||||
| PIK | (1.75%) | (1.75%) | (1.75%) | (1.75%) | (1.75%) | (1.75%) | (1.75%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ToroPrivateInvestmentsIILPMember | bcsf:ToroPrivateInvestmentsIILPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Toro Private Investments ll, LP First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% | 1.50% |
| Interest rate | 12.42% | 9.75% | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | 9.75% | 9.75% | 9.75% | 9.75% | 9.75% | 9.75% |
| Maturity date | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 | Feb. 28, 2025 |
| Principal/Shares | $ 394 | $ 366 | ||||||||||||
| Investments, amortized cost | 391 | 363 | ||||||||||||
| Investments at fair value | $ 391 | $ 377 | ||||||||||||
| PIK | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) | (7.25%) |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ToroPrivateInvestmentsIILPMember | bcsf:ToroPrivateInvestmentsIILPMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Transportation Consumer [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] | Transportation Consumer Non Controlled Non Affiliate [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Utimaco, Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | |||||||||||||
| Investments, amortized cost | 2,123 | |||||||||||||
| Investments at fair value | $ 2,006 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Utimaco, Inc. First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.58% | 6.58% | 6.58% | 6.58% | 6.58% | 6.58% | 6.58% | |||||||
| Maturity date | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | |||||||
| Principal/Shares | $ 92 | |||||||||||||
| Investments, amortized cost | 100 | |||||||||||||
| Investments at fair value | $ 91 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: Utimaco, Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | |||||||
| Interest rate | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% | |||||||
| Maturity date | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | |||||||
| Principal/Shares | $ 148 | |||||||||||||
| Investments, amortized cost | 146 | |||||||||||||
| Investments at fair value | $ 148 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Utimaco, Inc. First Lien Senior Secured Loan Sofr 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | |||||||
| Maturity date | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | |||||||
| Principal/Shares | $ 128 | |||||||||||||
| Investments, amortized cost | 127 | |||||||||||||
| Investments at fair value | $ 128 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Utimaco, Inc. First Lien Senior Secured Loan Sofr 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | |||||||
| Maturity date | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | |||||||
| Principal/Shares | $ 262 | |||||||||||||
| Investments, amortized cost | 259 | |||||||||||||
| Investments at fair value | $ 262 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| Investment, Identifier [Axis]: Utimaco, Inc. Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 1 | |||||||||||||
| Investments, amortized cost | 2,123 | |||||||||||||
| Investments at fair value | $ 2,006 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: V Global Holdings LLCFirst Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 6.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 8.99% | 7.00% | 8.99% | 8.99% | 8.99% | 8.99% | 8.99% | 8.99% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 |
| Principal/Shares | $ 5,876 | $ 24,813 | ||||||||||||
| Investments, amortized cost | 5,795 | 24,242 | ||||||||||||
| Investments at fair value | $ 5,772 | $ 24,813 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | V Global Holdings L L C [Member] | V Global Holdings L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: V Global Holdings LLCFirst Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% |
| Interest rate | 8.45% | 8.25% | 8.45% | 8.45% | 8.45% | 8.45% | 8.45% | 8.45% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% | 8.25% |
| Maturity date | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 | Dec. 22, 2025 |
| Principal/Shares | $ 1,351 | $ 2,050 | ||||||||||||
| Investments, amortized cost | 1,192 | 1,893 | ||||||||||||
| Investments at fair value | $ 1,182 | $ 2,050 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | V Global Holdings L L C [Member] | V Global Holdings L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | us-gaap:PrimeRateMember | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember |
| Investment, Identifier [Axis]: V Global Holdings Llc First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | |||||||
| Principal/Shares | € | € 100 | |||||||||||||
| Investments, amortized cost | $ 103 | |||||||||||||
| Investments at fair value | $ 97 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | V Global Holdings L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: VPARK BIDCO AB First Lien Senior Secured Loan Cibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% |
| Interest rate | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Maturity date | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 |
| Principal/Shares | € 570 | kr 570 | ||||||||||||
| Investments, amortized cost | $ 92 | 92 | ||||||||||||
| Investments at fair value | $ 75 | kr 87 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:VPARKBIDCOABMember | bcsf:VPARKBIDCOABMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember |
| Investment, Identifier [Axis]: VPARK BIDCO AB First Lien Senior Secured Loan Nibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% |
| Interest rate | 6.60% | 4.75% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Maturity date | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 |
| Principal/Shares | $ 740 | kr 740 | ||||||||||||
| Investments, amortized cost | 93 | 93 | ||||||||||||
| Investments at fair value | $ 68 | kr 84 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:VPARKBIDCOABMember | bcsf:VPARKBIDCOABMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember |
| Investment, Identifier [Axis]: Ventiv Holdco, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | |||||||
| Investments at fair value | $ (68) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | Ventiv Holdco, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: Ventiv Holdco, Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.17% | 6.50% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 |
| Principal/Shares | $ 13,807 | $ 23,812 | ||||||||||||
| Investments, amortized cost | 13,693 | 23,576 | ||||||||||||
| Investments at fair value | $ 13,531 | $ 23,812 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Ventiv Holdco, Inc [Member] | Ventiv Holdco, Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: Ventiv Topco, Inc. Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 28 | $ 28 | ||||||||||||
| Investments, amortized cost | 2,833 | 2,833 | ||||||||||||
| Investments at fair value | $ 2,121 | $ 2,755 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:VentivTopcoIncMember | bcsf:VentivTopcoIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Identifier [Axis]: Ventiv Topco, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | Sep. 03, 2025 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:VentivTopcoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Identifier [Axis]: WCI Gigawatt Purchaser DD T/L First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | |||||||
| Principal/Shares | $ 3,182 | |||||||||||||
| Investments, amortized cost | 3,076 | |||||||||||||
| Investments at fair value | $ 3,074 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | W C I Gigawatt Purchaser D D T L [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WCI Gigawatt Purchaser First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | |||||||
| Maturity date | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | |||||||
| Principal/Shares | $ 1,447 | |||||||||||||
| Investments, amortized cost | 1,446 | |||||||||||||
| Investments at fair value | $ 1,415 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCIGigawattPurchaserMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WCI Gigawatt Purchaser First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | 8.73% | |||||||
| Maturity date | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | |||||||
| Principal/Shares | $ 3,195 | |||||||||||||
| Investments, amortized cost | 3,101 | |||||||||||||
| Investments at fair value | $ 3,086 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCIGigawattPurchaserMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WCI Gigawatt Purchaser First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.51% | 8.51% | 8.51% | 8.51% | 8.51% | 8.51% | 8.51% | |||||||
| Maturity date | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | |||||||
| Principal/Shares | $ 965 | |||||||||||||
| Investments, amortized cost | 903 | |||||||||||||
| Investments at fair value | $ 893 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCIGigawattPurchaserMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WCI Gigawatt Purchaser R/C First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | |||||||
| Investments at fair value | $ (72) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCIGigawattPurchaserRCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: WCI Gigawatt Purchaser T/L First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | Nov. 19, 2027 | |||||||
| Principal/Shares | $ 22,304 | |||||||||||||
| Investments, amortized cost | 21,809 | |||||||||||||
| Investments at fair value | $ 21,802 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCIGigawattPurchaserTLMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WCI-HSG HOLDCO, LLC Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 675 | $ 675 | ||||||||||||
| Investments, amortized cost | 675 | 675 | ||||||||||||
| Investments at fair value | $ 2,217 | $ 1,993 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCI-HSGHOLDCOLLCMember | bcsf:WCI-HSGHOLDCOLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Identifier [Axis]: WCI-HSG Purchaser, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.75% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Interest rate | 7.62% | 5.75% | 7.62% | 7.62% | 7.62% | 7.62% | 7.62% | 7.62% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Maturity date | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 |
| Principal/Shares | $ 8,644 | $ 17,422 | ||||||||||||
| Investments, amortized cost | 8,591 | 17,285 | ||||||||||||
| Investments at fair value | $ 8,644 | $ 17,422 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCI-HSGPurchaserIncMember | bcsf:WCI-HSGPurchaserIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: WCI-HSG Purchaser, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Feb. 22, 2025 | Feb. 24, 2025 | Feb. 22, 2025 | Feb. 22, 2025 | Feb. 22, 2025 | Feb. 22, 2025 | Feb. 22, 2025 | Feb. 22, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 | Feb. 24, 2025 |
| Principal/Shares | $ 1,209 | |||||||||||||
| Investments, amortized cost | 1,190 | |||||||||||||
| Investments at fair value | $ 1,209 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WCI-HSGPurchaserIncMember | bcsf:WCI-HSGPurchaserIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WP CPP Holdings, LLC Senior Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% |
| Interest rate | 10.56% | 8.75% | 10.56% | 10.56% | 10.56% | 10.56% | 10.56% | 10.56% | 8.75% | 8.75% | 8.75% | 8.75% | 8.75% | 8.75% |
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Principal/Shares | $ 11,724 | $ 11,724 | ||||||||||||
| Investments, amortized cost | 11,658 | 11,646 | ||||||||||||
| Investments at fair value | $ 10,815 | $ 11,495 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WPCPPHoldingsLLCMember | bcsf:WPCPPHoldingsLLCMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: WSP Initial Term Loan First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.37% | 9.37% | 9.37% | 9.37% | 9.37% | 9.37% | 9.37% | |||||||
| Maturity date | Apr. 27, 2027 | Apr. 27, 2023 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2023 | Apr. 27, 2023 | Apr. 27, 2023 | Apr. 27, 2023 | Apr. 27, 2023 | Apr. 27, 2023 |
| Principal/Shares | $ 6,018 | |||||||||||||
| Investments, amortized cost | 5,916 | |||||||||||||
| Investments at fair value | $ 5,626 | $ (31) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | WSP Initial Term Loan | WSP Initial Term Loan | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WSP Initial Term Loan First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | |||||||
| Investments at fair value | $ (117) | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WSP Initial Term Loan | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | |||||||
| Investment, Identifier [Axis]: WSP Initial Term Loan First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | 7.25% | |||||||
| Maturity date | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | |||||||
| Principal/Shares | $ 12,251 | |||||||||||||
| Investments, amortized cost | 12,017 | |||||||||||||
| Investments at fair value | $ 12,037 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WSP Initial Term Loan | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WSP LP Interest Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 2,898 | $ 2,898 | ||||||||||||
| Investments, amortized cost | 2,898 | 2,898 | ||||||||||||
| Investments at fair value | $ 1,559 | $ 2,829 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WSPLPInterestMember | bcsf:WSPLPInterestMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] |
| Investment, Identifier [Axis]: WSP Revolving Loan First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 | Apr. 27, 2027 |
| Principal/Shares | $ 47 | |||||||||||||
| Investments, amortized cost | 40 | |||||||||||||
| Investments at fair value | $ 18 | $ (8) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WSPLPInterestMember | WSP Revolving Loan | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] | Consumer Goods Wholesale Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WU Holdco, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.17% | 6.50% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 |
| Principal/Shares | $ 37,775 | $ 44,452 | ||||||||||||
| Investments, amortized cost | 37,341 | 43,847 | ||||||||||||
| Investments at fair value | $ 35,886 | $ 44,452 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | WU Holdco, Inc. | WU Holdco, Inc. | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: WU Holdco, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | 9.17% | |||||||
| Maturity date | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | |||||||
| Principal/Shares | $ 1,704 | |||||||||||||
| Investments, amortized cost | 1,677 | |||||||||||||
| Investments at fair value | $ 1,619 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WU Holdco, Inc. | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WU Holdco, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.72% | 5.72% | 5.72% | 5.72% | 5.72% | 5.72% | 5.72% | |||||||
| Maturity date | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | |||||||
| Principal/Shares | $ 1,690 | |||||||||||||
| Investments, amortized cost | 1,656 | |||||||||||||
| Investments at fair value | $ 1,690 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WU Holdco, Inc. | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WU Holdco, Inc. First Lien Senior Secured Loan - Revolver Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.14% | 9.14% | 9.14% | 9.14% | 9.14% | 9.14% | 9.14% | |||||||
| Maturity date | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | Mar. 26, 2025 | |||||||
| Principal/Shares | $ 2,930 | |||||||||||||
| Investments, amortized cost | 2,904 | |||||||||||||
| Investments at fair value | $ 2,648 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WU Holdco, Inc. | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WU Holdco, Inc. First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | |||||||
| Principal/Shares | $ 6,594 | |||||||||||||
| Investments, amortized cost | 6,534 | |||||||||||||
| Investments at fair value | $ 6,594 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WU Holdco, Inc. | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: WU Holdco, Inc. First Lien Senior Secured Loan Libor One | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | Mar. 26, 2026 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | WU Holdco, Inc. | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Identifier [Axis]: Walker Edison First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | 12.42% | |||||||
| Maturity date | Mar. 31, 2027 | Mar. 31, 2027 | Mar. 31, 2027 | Mar. 31, 2027 | Mar. 31, 2027 | Mar. 31, 2027 | Mar. 31, 2027 | |||||||
| Principal/Shares | $ 20,912 | |||||||||||||
| Investments, amortized cost | 20,736 | |||||||||||||
| Investments at fair value | $ 14,220 | |||||||||||||
| PIK | (3.00%) | (3.00%) | (3.00%) | (3.00%) | (3.00%) | (3.00%) | (3.00%) | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Walker Edison Initial Term Loan First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.75% | 9.75% | 9.75% | 9.75% | 9.75% | 9.75% | 9.75% | |||||||
| Maturity date | Aug. 05, 2027 | Aug. 05, 2027 | Aug. 05, 2027 | Aug. 05, 2027 | Aug. 05, 2027 | Aug. 05, 2027 | Aug. 05, 2027 | |||||||
| Principal/Shares | $ 20,447 | |||||||||||||
| Investments, amortized cost | 20,248 | |||||||||||||
| Investments at fair value | $ 19,627 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:WalkerEdisonInitialTermLoanMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Whitcraft LLC First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 |
| Principal/Shares | $ 28,760 | |||||||||||||
| Investments, amortized cost | 28,705 | |||||||||||||
| Investments at fair value | $ 27,466 | $ (59) | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Whitcraft L L C [Member] | Whitcraft L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Whitcraft LLC Senior Secured Loan First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 6.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 11.25% | 7.00% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 11.25% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 | Apr. 03, 2023 |
| Principal/Shares | $ 254 | $ 39,775 | ||||||||||||
| Investments, amortized cost | 251 | 39,594 | ||||||||||||
| Investments at fair value | $ 172 | $ 38,482 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | Whitcraft L L C [Member] | Whitcraft L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:PrimeRateMember | London Interbank Offered Rate (LIBOR) [Member] | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | us-gaap:PrimeRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: World Insurance First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | |||||||
| Principal/Shares | $ 3,144 | |||||||||||||
| Investments, amortized cost | 3,088 | |||||||||||||
| Investments at fair value | $ 3,121 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | World Insurance [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: World Insurance First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | |||||||
| Principal/Shares | $ 8,358 | |||||||||||||
| Investments, amortized cost | 8,285 | |||||||||||||
| Investments at fair value | $ 8,296 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | World Insurance [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: World Insurance First Lien Senior Secured Loan - Delayed Draw Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | |||||||
| Maturity date | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | |||||||
| Principal/Shares | $ 8,295 | |||||||||||||
| Investments, amortized cost | 8,236 | |||||||||||||
| Investments at fair value | $ 8,295 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | World Insurance [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: World Insurance First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | |||||||
| Principal/Shares | $ 70 | |||||||||||||
| Investments, amortized cost | 54 | |||||||||||||
| Investments at fair value | $ 63 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | World Insurance [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: World Insurance First Lien Senior Secured Loan - Revolver Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | |||||||
| Maturity date | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | |||||||
| Principal/Shares | $ 256 | |||||||||||||
| Investments, amortized cost | 243 | |||||||||||||
| Investments at fair value | $ 256 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | World Insurance [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: World Insurance First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | 9.30% | |||||||
| Maturity date | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | Apr. 01, 2026 | |||||||
| Principal/Shares | $ 3,122 | |||||||||||||
| Investments, amortized cost | 3,075 | |||||||||||||
| Investments at fair value | $ 3,122 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | World Insurance [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: YLG Holdings, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 7.10% | 6.25% | 7.10% | 7.10% | 7.10% | 7.10% | 7.10% | 7.10% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | |||||||
| Principal/Shares | $ 27,221 | $ 38,086 | ||||||||||||
| Investments, amortized cost | 27,124 | 37,900 | ||||||||||||
| Investments at fair value | $ 27,153 | $ 38,086 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | YLG Holdings, Inc. | YLG Holdings, Inc. | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: YLG Holdings, Inc. First Lien Senior Secured Loan - Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 6.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 7.08% | 7.00% | 7.08% | 7.08% | 7.08% | 7.08% | 7.08% | 7.08% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 |
| Principal/Shares | $ 5,022 | $ 5,060 | ||||||||||||
| Investments, amortized cost | 5,017 | 5,055 | ||||||||||||
| Investments at fair value | $ 5,009 | $ 5,060 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | YLG Holdings, Inc. | YLG Holdings, Inc. | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| Investment, Identifier [Axis]: YLG Holdings, Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 7.93% | 7.93% | 7.93% | 7.93% | 7.93% | 7.93% | 7.93% | |||||||
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 |
| Principal/Shares | $ 855 | |||||||||||||
| Investments, amortized cost | 811 | |||||||||||||
| Investments at fair value | $ 833 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | YLG Holdings, Inc. | YLG Holdings, Inc. | ||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | Construction and Building | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember | bcsf:ConstructionAndBuildingSectorMember |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: Zeppelin BidCo Pty Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 6.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 7.12% | 5.12% | 7.12% | 7.12% | 7.12% | 7.12% | 7.12% | 7.12% | 5.12% | 5.12% | 5.12% | 5.12% | 5.12% | 5.12% |
| Maturity date | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 |
| Principal/Shares | $ 206 | $ 206 | ||||||||||||
| Investments, amortized cost | $ 142 | 142 | ||||||||||||
| Investments at fair value | $ 131 | $ 150 | ||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ZeppelinBidCoPtyLimitedMember | bcsf:ZeppelinBidCoPtyLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember |
| Investment, Identifier [Axis]: iBanFirst Facility B First Lien Senior Secured Loan Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Principal/Shares | € | € 102 | |||||||||||||
| Investments, amortized cost | € | 128 | |||||||||||||
| Investments at fair value | € | € 116 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstFacilityBMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: iBanFirst Facility Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | € | € 7,112 | |||||||||||||
| Investments, amortized cost | $ 8,136 | |||||||||||||
| Investments at fair value | $ 9,252 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstFacilityMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: iBanFirst Facility Series A Preferred Units Preferred Equity | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 5,080 | |||||||||||||
| Investments, amortized cost | 5,996 | |||||||||||||
| Investments at fair value | $ 6,290 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstFacilitySeriesAPreferredUnitsMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | Preferred Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: iBanFirst First Lien Senior Secured Loan 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Principal/Shares | $ 2,748 | |||||||||||||
| Investments, amortized cost | 2,817 | |||||||||||||
| Investments at fair value | $ 2,694 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: iBanFirst First Lien Senior Secured Loan 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Principal/Shares | € | € 80 | |||||||||||||
| Investments, amortized cost | $ 83 | |||||||||||||
| Investments at fair value | $ 78 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: iBanFirst First Lien Senior Secured Loan Euribor | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: iBanFirst Revolving Facility First Lien Senior Secured Loan - Revolver Euibor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Principal/Shares | € | € 2,030 | |||||||||||||
| Investments, amortized cost | € | 2,244 | |||||||||||||
| Investments at fair value | € | € 2,308 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstRevolvingFacilityMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| Investment, Identifier [Axis]: masLabor Equity Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 345 | |||||||||||||
| Investments, amortized cost | 345 | |||||||||||||
| Investments at fair value | $ 372 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:masLaborEquityMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: masLabor Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 345 | |||||||||||||
| Investments, amortized cost | 345 | |||||||||||||
| Investments at fair value | $ 909 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:masLaborMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: masLabor First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Interest rate | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Maturity date | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | |||||||
| Principal/Shares | £ | £ 8,513 | |||||||||||||
| Investments, amortized cost | $ 8,289 | |||||||||||||
| Investments at fair value | $ 8,513 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:masLaborMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Investment, Identifier [Axis]: masLabor First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:masLaborMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: masLabor Revolver First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Maturity date | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | |||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:masLaborRevolverMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Identifier [Axis]: masLabor Term Loan Note First Lien Senior Secured Loan Libor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | |||||||
| Interest rate | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Maturity date | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | Jul. 01, 2027 | |||||||
| Principal/Shares | $ 8,578 | |||||||||||||
| Investments, amortized cost | 8,324 | |||||||||||||
| Investments at fair value | $ 8,578 | |||||||||||||
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:masLaborTermLoanNoteMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| Media: Advertising, Printing & Publishing | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 54,169 | $ 50,389 | ||||||||||||
| Investments at fair value | $ 27,819 | $ 39,459 | ||||||||||||
| % of Member's Equity | 2.50% | 3.60% | 2.50% | 2.50% | 2.50% | 2.50% | 2.50% | 2.50% | 3.60% | 3.60% | 3.60% | 3.60% | 3.60% | 3.60% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Aerospace Sector [Member] | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 398,665 | $ 309,458 | ||||||||||||
| Investments at fair value | 380,118 | 282,598 | ||||||||||||
| Automotive Sector [Member] | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | 78,189 | 87,597 | ||||||||||||
| Investments at fair value | $ 78,215 | $ 88,555 | ||||||||||||
| % of Member's Equity | 7.10% | 8.10% | 7.10% | 7.10% | 7.10% | 7.10% | 7.10% | 7.10% | 8.10% | 8.10% | 8.10% | 8.10% | 8.10% | 8.10% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Banking [Member] | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 7,736 | $ 18,370 | ||||||||||||
| Investments at fair value | $ 7,980 | $ 18,690 | ||||||||||||
| % of Member's Equity | 0.70% | 1.70% | 0.70% | 0.70% | 0.70% | 0.70% | 0.70% | 0.70% | 1.70% | 1.70% | 1.70% | 1.70% | 1.70% | 1.70% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | |||||||
| Chemicals, Plastics & Rubber | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 14,177 | $ 26,135 | ||||||||||||
| Investments at fair value | $ 14,065 | $ 26,863 | ||||||||||||
| % of Member's Equity | 1.30% | 2.40% | 1.30% | 1.30% | 1.30% | 1.30% | 1.30% | 1.30% | 2.40% | 2.40% | 2.40% | 2.40% | 2.40% | 2.40% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Construction and Building | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 117,017 | $ 70,256 | ||||||||||||
| Investments at fair value | $ 113,634 | $ 68,570 | ||||||||||||
| % of Member's Equity | 10.40% | 6.20% | 10.40% | 10.40% | 10.40% | 10.40% | 10.40% | 10.40% | 6.20% | 6.20% | 6.20% | 6.20% | 6.20% | 6.20% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Containers, Packaging and Glass | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 16,372 | $ 27,379 | ||||||||||||
| Investments at fair value | 16,071 | 27,378 | ||||||||||||
| Energy: Oil and Gas | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | 57,002 | 69,588 | ||||||||||||
| Investments at fair value | 74,898 | 79,548 | ||||||||||||
| Fire Finance | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | 49,741 | 24,245 | ||||||||||||
| Investments at fair value | $ 47,545 | $ 24,452 | ||||||||||||
| % of Member's Equity | 2.30% | 2.20% | 2.30% | 2.30% | 2.30% | 2.30% | 2.30% | 2.30% | 2.20% | 2.20% | 2.20% | 2.20% | 2.20% | 2.20% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Fire Insurance | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 64,944 | $ 62,165 | ||||||||||||
| Investments at fair value | $ 62,954 | $ 63,123 | ||||||||||||
| % of Member's Equity | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Healthcare and Pharmaceuticals | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 101,715 | $ 102,116 | ||||||||||||
| Investments at fair value | 99,633 | 100,771 | ||||||||||||
| Media: Diversified & Production | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | 36,721 | 46,420 | ||||||||||||
| Investments at fair value | $ 34,136 | $ 44,835 | ||||||||||||
| % of Member's Equity | 3.10% | 4.10% | 3.10% | 3.10% | 3.10% | 3.10% | 3.10% | 3.10% | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Media: Broadcasting & Subscription | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 2,825 | $ 8,740 | ||||||||||||
| Investments at fair value | $ 2,717 | $ 8,979 | ||||||||||||
| % of Member's Equity | 0.20% | 0.80% | 0.20% | 0.20% | 0.20% | 0.20% | 0.20% | 0.20% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% | 0.80% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| High Tech Industries | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 220,512 | $ 182,811 | ||||||||||||
| Investments at fair value | 217,497 | 183,069 | ||||||||||||
| Hotel, Gaming & Leisure | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | 37,159 | 53,232 | ||||||||||||
| Investments at fair value | $ 36,068 | $ 51,956 | ||||||||||||
| % of Member's Equity | 3.30% | 4.70% | 3.30% | 3.30% | 3.30% | 3.30% | 3.30% | 3.30% | 4.70% | 4.70% | 4.70% | 4.70% | 4.70% | 4.70% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Retail Sector | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 60,350 | $ 83,036 | ||||||||||||
| Investments at fair value | 53,266 | 83,064 | ||||||||||||
| Services, Business | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | 170,902 | 226,035 | ||||||||||||
| Investments at fair value | $ 163,918 | $ 225,437 | ||||||||||||
| % of Member's Equity | 15.00% | 20.50% | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | 15.00% | 20.50% | 20.50% | 20.50% | 20.50% | 20.50% | 20.50% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Services, Consumer [Business] | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 17,585 | $ 40,467 | ||||||||||||
| Investments at fair value | $ 17,823 | $ 41,236 | ||||||||||||
| % of Member's Equity | 1.60% | 3.70% | 1.60% | 1.60% | 1.60% | 1.60% | 1.60% | 1.60% | 3.70% | 3.70% | 3.70% | 3.70% | 3.70% | 3.70% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| Wholesale | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 26,426 | $ 77,737 | ||||||||||||
| Investments at fair value | $ 27,640 | $ 80,070 | ||||||||||||
| % of Member's Equity | 2.50% | 7.30% | 2.50% | 2.50% | 2.50% | 2.50% | 2.50% | 2.50% | 7.30% | 7.30% | 7.30% | 7.30% | 7.30% | 7.30% |
| Investment, Issuer Affiliation [Extensible Enumeration] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] | Investment, Unaffiliated Issuer [Member] |
| International Senior Loan Program, LLC | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 698,650 | $ 512,712 | ||||||||||||
| Investments at fair value | $ 623,017 | $ 501,545 | ||||||||||||
| % of Member's Equity | 830.70% | 805.50% | 830.70% | 830.70% | 830.70% | 830.70% | 830.70% | 830.70% | 805.50% | 805.50% | 805.50% | 805.50% | 805.50% | 805.50% |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: 9 Story Media Group Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.50% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 9.03% | 6.25% | 9.03% | 9.03% | 9.03% | 9.03% | 9.03% | 9.03% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Principal/Shares | $ 6,816 | $ 7,164 | ||||||||||||
| Investments, amortized cost | 5,411 | 5,688 | ||||||||||||
| Investments at fair value | $ 4,929 | $ 5,669 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Nine Story Media Group Inc [Member] | Nine Story Media Group Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: 9 Story Media Group Inc. First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.50% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Interest rate | 5.83% | 6.25% | 5.83% | 5.83% | 5.83% | 5.83% | 5.83% | 5.83% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Principal/Shares | € 3,674 | $ 16 | ||||||||||||
| Investments, amortized cost | 4,469 | 13 | ||||||||||||
| Investments at fair value | € 3,601 | $ 13 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Nine Story Media Group Inc [Member] | Nine Story Media Group Inc [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: 9 Story Media Group Inc. First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | |||||||
| Principal/Shares | € | € 3,859 | |||||||||||||
| Investments, amortized cost | € | 4,694 | |||||||||||||
| Investments at fair value | € | € 4,388 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Nine Story Media Group Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Ansett Aviation Training First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.69% | 4.69% | 4.69% | 4.69% | 4.69% | 4.69% | 4.69% | |||||||
| Interest rate | 5.69% | 5.69% | 5.69% | 5.69% | 5.69% | 5.69% | 5.69% | |||||||
| Maturity date | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | Sep. 24, 2031 | |||||||
| Principal/Shares | $ 14,144 | |||||||||||||
| Investments, amortized cost | 9,830 | |||||||||||||
| Investments at fair value | $ 9,052 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AnsettAviationTrainingMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Ansett Aviation Training Equity Interest | ||||||||||||||
| Investments | ||||||||||||||
| Principal/Shares | $ 10,238 | |||||||||||||
| Investments, amortized cost | 7,115 | |||||||||||||
| Investments at fair value | $ 6,552 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:AnsettAviationTrainingMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | Common Stock [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Aptus 1724 Gmbh First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 6.78% | 6.25% | 6.78% | 6.78% | 6.78% | 6.78% | 6.78% | 6.78% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% |
| Maturity date | Aug. 23, 2027 | Feb. 23, 2028 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 | Feb. 23, 2028 |
| Principal/Shares | € | € 35,000 | € 35,000 | ||||||||||||
| Investments, amortized cost | € | 41,063 | 40,944 | ||||||||||||
| Investments at fair value | € | € 33,706 | € 39,795 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Aptus1724GmbhMember | bcsf:Aptus1724GmbhMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Aptus 1724 Gmbh First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | 9.39% | |||||||
| Maturity date | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | Aug. 23, 2027 | |||||||
| Principal/Shares | $ 10,000 | |||||||||||||
| Investments, amortized cost | 9,939 | |||||||||||||
| Investments at fair value | $ 9,875 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Aptus1724GmbhMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Armstrong Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Maturity date | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | Apr. 30, 2025 | |||||||
| Principal/Shares | £ | £ 5,602 | |||||||||||||
| Investments, amortized cost | £ | 7,711 | |||||||||||||
| Investments at fair value | £ | £ 7,581 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ArmstrongBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Avalon Acquiror, Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 9.80% | 9.80% | 9.80% | 9.80% | 9.80% | 9.80% | 9.80% | |||||||
| Maturity date | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | Mar. 10, 2028 | |||||||
| Principal/Shares | $ 11,970 | |||||||||||||
| Investments, amortized cost | 11,858 | |||||||||||||
| Investments at fair value | $ 11,761 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Avalon Acquiror, Inc [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: B T M Comms Jersey Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | |||||||
| Interest rate | 7.09% | 7.09% | 7.09% | 7.09% | 7.09% | 7.09% | 7.09% | |||||||
| Maturity date | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | |||||||
| Principal/Shares | $ 9,653 | |||||||||||||
| Investments, amortized cost | 9,572 | |||||||||||||
| Investments at fair value | $ 9,653 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BTMCommsJerseyLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan, One | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | |||||||
| Interest rate | 8.06% | 8.06% | 8.06% | 8.06% | 8.06% | 8.06% | 8.06% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 21,739 | |||||||||||||
| Investments, amortized cost | £ | 29,552 | |||||||||||||
| Investments at fair value | £ | £ 24,283 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoILimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan, Three | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | |||||||
| Interest rate | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 6,582 | |||||||||||||
| Investments, amortized cost | £ | 8,807 | |||||||||||||
| Investments at fair value | £ | £ 7,352 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoILimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Brook Bidco I Limited First Lien Senior Secured Loan, Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | 3.00% | |||||||
| Interest rate | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | 9.18% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 4,747 | |||||||||||||
| Investments, amortized cost | £ | 6,351 | |||||||||||||
| Investments at fair value | £ | £ 5,302 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:BrookBidcoILimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: CB Nike IntermediateCo Ltd First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Interest rate | 7.56% | 5.75% | 7.56% | 7.56% | 7.56% | 7.56% | 7.56% | 7.56% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 |
| Principal/Shares | $ 34,104 | $ 34,367 | ||||||||||||
| Investments, amortized cost | 34,104 | 34,367 | ||||||||||||
| Investments at fair value | $ 34,104 | $ 34,367 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | C B Nike Intermediate Co Ltd [Member] | C B Nike Intermediate Co Ltd [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries [Member] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: CB Nike IntermediateCo Ltd First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | |||||||
| Interest rate | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Maturity date | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | Oct. 31, 2025 | |||||||
| Principal/Shares | $ 4,384 | |||||||||||||
| Investments, amortized cost | 4,384 | |||||||||||||
| Investments at fair value | $ 4,384 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | C B Nike Intermediate Co Ltd [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: CST Buyer Company First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.55% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% |
| Interest rate | 8.62% | 6.50% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 8.62% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 | Oct. 03, 2025 |
| Principal/Shares | $ 14,855 | $ 14,927 | ||||||||||||
| Investments, amortized cost | 14,855 | 14,927 | ||||||||||||
| Investments at fair value | $ 14,853 | $ 14,927 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | C S T Buyer Company [Member] | C S T Buyer Company [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Cardo First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | |||||||
| Maturity date | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | May 12, 2028 | |||||||
| Principal/Shares | $ 9,653 | |||||||||||||
| Investments, amortized cost | 9,560 | |||||||||||||
| Investments at fair value | $ 9,653 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:CardoMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Caribou Bidco Limited First Lien Senior Secured Loan, One | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | |||||||
| Maturity date | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | |||||||
| Principal/Shares | £ | £ 1,577 | |||||||||||||
| Investments, amortized cost | £ | 1,951 | |||||||||||||
| Investments at fair value | £ | £ 1,761 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Caribou Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Caribou Bidco Limited First Lien Senior Secured Loan, Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | 7.19% | |||||||
| Maturity date | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | Jan. 29, 2029 | |||||||
| Principal/Shares | £ | £ 19,500 | |||||||||||||
| Investments, amortized cost | £ | 24,141 | |||||||||||||
| Investments at fair value | £ | £ 21,782 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Caribou Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Chamber Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 6.00% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 7.85% | 6.50% | 7.85% | 7.85% | 7.85% | 7.85% | 7.85% | 7.85% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 | Jun. 07, 2028 |
| Principal/Shares | $ 23,423 | $ 23,423 | ||||||||||||
| Investments, amortized cost | 23,225 | 23,198 | ||||||||||||
| Investments at fair value | $ 23,423 | $ 23,423 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ChamberBidcoLimitedMember | bcsf:ChamberBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Comet Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% |
| Interest rate | 5.29% | 5.42% | 5.29% | 5.29% | 5.29% | 5.29% | 5.29% | 5.29% | 5.42% | 5.42% | 5.42% | 5.42% | 5.42% | 5.42% |
| Maturity date | Sep. 30, 2024 | Sep. 27, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 30, 2024 | Sep. 27, 2024 | Sep. 27, 2024 | Sep. 27, 2024 | Sep. 27, 2024 | Sep. 27, 2024 | Sep. 27, 2024 |
| Principal/Shares | £ | £ 7,362 | £ 7,362 | ||||||||||||
| Investments, amortized cost | £ | 9,603 | 9,460 | ||||||||||||
| Investments at fair value | £ | £ 5,715 | £ 9,249 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:CometBidcoLimitedMember | bcsf:CometBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Condor Finco S R L First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Principal/Shares | € | € 10,580 | |||||||||||||
| Investments, amortized cost | € | 11,974 | |||||||||||||
| Investments at fair value | € | € 10,371 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:CondorFincoSrlMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Datix Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | |||||||
| Interest rate | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | 4.25% | |||||||
| Maturity date | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | |||||||
| Principal/Shares | $ 4,169 | |||||||||||||
| Investments, amortized cost | 3,289 | |||||||||||||
| Investments at fair value | $ 3,028 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DatixBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Datix Bidco Limited First Lien Senior Secured Loan - Revolver | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% | 4.50% |
| Interest rate | 4.57% | 4.96% | 4.57% | 4.57% | 4.57% | 4.57% | 4.57% | 4.57% | 4.96% | 4.96% | 4.96% | 4.96% | 4.96% | 4.96% |
| Maturity date | Apr. 28, 2025 | Oct. 28, 2024 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Apr. 28, 2025 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 | Oct. 28, 2024 |
| Principal/Shares | $ 4,169 | £ 12,013 | ||||||||||||
| Investments, amortized cost | £ | £ 3,291 | 16,916 | ||||||||||||
| Investments at fair value | $ 2,608 | £ 16,255 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DatixBidcoLimitedMember | bcsf:DatixBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember | bcsf:FirstLienSeniorSecuredLoanRevolverMember |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare and Pharmaceuticals | Healthcare And Pharmaceuticals [Member] | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapRateMember | London Interbank Offered Rate (LIBOR) [Member] | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | bcsf:BankBillSwapRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Datix Bidco Limited Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% | 7.75% |
| Interest rate | 9.44% | 8.21% | 9.44% | 9.44% | 9.44% | 9.44% | 9.44% | 9.44% | 8.21% | 8.21% | 8.21% | 8.21% | 8.21% | 8.21% |
| Maturity date | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 | Apr. 27, 2026 |
| Principal/Shares | £ | £ 12,013 | £ 963 | ||||||||||||
| Investments, amortized cost | £ | 16,916 | 1,323 | ||||||||||||
| Investments at fair value | £ | £ 13,083 | £ 1,303 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:DatixBidcoLimitedMember | bcsf:DatixBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare and Pharmaceuticals | Healthcare And Pharmaceuticals [Member] | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | London Interbank Offered Rate (LIBOR) [Member] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Golden State Buyer Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Interest rate | 8.92% | 5.50% | 8.92% | 8.92% | 8.92% | 8.92% | 8.92% | 8.92% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% |
| Maturity date | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 | Jun. 22, 2026 |
| Principal/Shares | $ 14,124 | $ 14,779 | ||||||||||||
| Investments, amortized cost | 14,068 | 14,709 | ||||||||||||
| Investments at fair value | $ 13,347 | $ 14,733 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:GoldenStateBuyerIncMember | bcsf:GoldenStateBuyerIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: International Entertainment Investments Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Interest rate | 6.47% | 5.06% | 6.47% | 6.47% | 6.47% | 6.47% | 6.47% | 6.47% | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% | 5.06% |
| Maturity date | May 31, 2025 | May 31, 2023 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2025 | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 | May 31, 2023 |
| Principal/Shares | £ | £ 8,753 | £ 8,734 | ||||||||||||
| Investments, amortized cost | £ | 12,316 | 12,255 | ||||||||||||
| Investments at fair value | £ | £ 9,777 | £ 11,782 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:InternationalEntertainmentInvestmentsLimitedMember | bcsf:InternationalEntertainmentInvestmentsLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: LEAP Legal Software PTY Ltd First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | 6.75% | |||||||
| Maturity date | Mar. 12, 2025 | Mar. 12, 2025 | Mar. 12, 2025 | Mar. 12, 2025 | Mar. 12, 2025 | Mar. 12, 2025 | Mar. 12, 2025 | |||||||
| Principal/Shares | $ 30,093 | |||||||||||||
| Investments, amortized cost | 22,867 | |||||||||||||
| Investments at fair value | $ 21,856 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LeapLegalSoftwarePTYLtdMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Learning Pool Facility B First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 6.09% | 6.09% | 6.09% | 6.09% | 6.09% | 6.09% | 6.09% | |||||||
| Maturity date | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | Jul. 07, 2028 | |||||||
| Principal/Shares | £ | £ 21,000 | |||||||||||||
| Investments, amortized cost | £ | 28,584 | |||||||||||||
| Investments at fair value | £ | £ 28,417 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LearningPoolMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Lightning Finco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | |||||||
| Principal/Shares | € | € 2,619 | |||||||||||||
| Investments, amortized cost | € | 2,951 | |||||||||||||
| Investments at fair value | € | € 2,567 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LightningFincoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Lightning Finco Limited First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 8.57% | 8.57% | 8.57% | 8.57% | 8.57% | 8.57% | 8.57% | |||||||
| Maturity date | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | Sep. 01, 2028 | |||||||
| Principal/Shares | $ 23,907 | |||||||||||||
| Investments, amortized cost | 23,721 | |||||||||||||
| Investments at fair value | $ 23,907 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:LightningFincoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: MRH Trowe Beteiligungsgesellschaft MBH First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | 5.70% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | |||||||
| Principal/Shares | € | € 21,335 | |||||||||||||
| Investments, amortized cost | € | 24,541 | |||||||||||||
| Investments at fair value | € | € 20,703 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MrhTroweBeteiligungsgesellschaftMBHMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: MRHT Facility A First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Maturity date | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | Jul. 26, 2028 | |||||||
| Principal/Shares | € | € 21,335 | |||||||||||||
| Investments, amortized cost | € | 24,521 | |||||||||||||
| Investments at fair value | € | € 24,257 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MRHTFacilityAMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Mertus 522. GmbH First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | |||||||
| Principal/Shares | € | € 22,244 | |||||||||||||
| Investments, amortized cost | € | 26,830 | |||||||||||||
| Investments at fair value | € | € 25,291 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Mertus522GmbHMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Mertus 522. GmbH First Lien Senior Secured Loan—Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | |||||||
| Principal/Shares | € | € 12,999 | |||||||||||||
| Investments, amortized cost | € | 15,680 | |||||||||||||
| Investments at fair value | € | € 14,780 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Mertus522GmbHMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Midcap Invest UK 1 Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.28% | 5.28% | 5.28% | 5.28% | 5.28% | 5.28% | 5.28% | |||||||
| Interest rate | 5.97% | 5.97% | 5.97% | 5.97% | 5.97% | 5.97% | 5.97% | |||||||
| Maturity date | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | |||||||
| Principal/Shares | £ | £ 12,151 | |||||||||||||
| Investments, amortized cost | £ | 16,361 | |||||||||||||
| Investments at fair value | £ | £ 13,573 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:MidcapInvestUK1BidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: New Look Vision Group First Lien Senior Secured Loan— Delayed Draw | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | 5.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 18,056 | |||||||||||||
| Investments, amortized cost | 14,752 | |||||||||||||
| Investments at fair value | $ 14,288 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | First Lien Senior Secured Loan Delayed Draw [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: New Look Vision Group Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 17,920 | |||||||||||||
| Investments, amortized cost | 14,660 | |||||||||||||
| Investments at fair value | $ 12,829 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: New Look Vision Group Inc. First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | 9.67% | |||||||
| Maturity date | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | May 26, 2028 | |||||||
| Principal/Shares | $ 3,510 | |||||||||||||
| Investments, amortized cost | € | € 2,708 | |||||||||||||
| Investments at fair value | $ 2,514 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | New Look Vision Group [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | bcsf:CanadianDollarOfferedRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Opus2 First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | 5.55% | |||||||
| Maturity date | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | May 05, 2028 | |||||||
| Principal/Shares | £ | £ 12,151 | |||||||||||||
| Investments, amortized cost | £ | 16,326 | |||||||||||||
| Investments at fair value | £ | £ 16,443 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Opus2Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Pack-A-Punch Bidco Limited First Lien Senior Secured Loan, One | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | 7.44% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | £ | £ 3,825 | |||||||||||||
| Investments, amortized cost | £ | 5,088 | |||||||||||||
| Investments at fair value | £ | £ 4,272 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PackaPunchBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Pack-A-Punch Bidco Limited First Lien Senior Secured Loan, Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 7.94% | 7.94% | 7.94% | 7.94% | 7.94% | 7.94% | 7.94% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | £ | £ 12,395 | |||||||||||||
| Investments, amortized cost | £ | 16,657 | |||||||||||||
| Investments at fair value | £ | £ 13,845 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PackaPunchBidcoLimitedMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Paisley Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | 5.50% | |||||||
| Interest rate | 6.19% | 6.19% | 6.19% | 6.19% | 6.19% | 6.19% | 6.19% | |||||||
| Maturity date | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | Nov. 26, 2028 | |||||||
| Principal/Shares | € | € 3,178 | |||||||||||||
| Investments, amortized cost | € | 3,367 | |||||||||||||
| Investments at fair value | € | € 3,115 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | Paisley Bidco Limited [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Parcel 2 Go Facility B First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 5.80% | 5.80% | 5.80% | 5.80% | 5.80% | 5.80% | 5.80% | |||||||
| Maturity date | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | Jul. 15, 2028 | |||||||
| Principal/Shares | £ | £ 12,395 | |||||||||||||
| Investments, amortized cost | £ | 16,619 | |||||||||||||
| Investments at fair value | £ | £ 16,689 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Parcel2GoFacilityBMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | bcsf:SterlingOvernightInterbankAverageRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Parmenion First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 6.69% | 6.69% | 6.69% | 6.69% | 6.69% | 6.69% | 6.69% | |||||||
| Maturity date | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | May 11, 2029 | |||||||
| Principal/Shares | £ | £ 32,300 | |||||||||||||
| Investments, amortized cost | £ | 39,063 | |||||||||||||
| Investments at fair value | £ | £ 36,079 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ParmenionMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Pharmathen Bidco B.V. First Lien Senior Secured Loan, One | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 5.98% | 5.98% | 5.98% | 5.98% | 5.98% | 5.98% | 5.98% | |||||||
| Maturity date | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | |||||||
| Principal/Shares | € | € 13,492 | |||||||||||||
| Investments, amortized cost | € | 14,957 | |||||||||||||
| Investments at fair value | € | € 13,192 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PharmathenBidcoBvMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Pharmathen Bidco B.V. First Lien Senior Secured Loan, Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 5.98% | 5.98% | 5.98% | 5.98% | 5.98% | 5.98% | 5.98% | |||||||
| Maturity date | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | Oct. 25, 2028 | |||||||
| Principal/Shares | € | € 358 | |||||||||||||
| Investments, amortized cost | € | 337 | |||||||||||||
| Investments at fair value | € | € 345 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:PharmathenBidcoBvMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: RH Diagnostik & Therapie Holding GmbH First Lien Senior Secured Loan, One | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 8.11% | 8.11% | 8.11% | 8.11% | 8.11% | 8.11% | 8.11% | |||||||
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | |||||||
| Principal/Shares | € | € 12,999 | |||||||||||||
| Investments, amortized cost | € | 15,695 | |||||||||||||
| Investments at fair value | € | € 12,487 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RhDiagnostikTherapieHoldingGmbhMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: RH Diagnostik & Therapie Holding GmbH First Lien Senior Secured Loan, Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Interest rate | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | 6.25% | |||||||
| Maturity date | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | May 28, 2026 | |||||||
| Principal/Shares | € | € 22,244 | |||||||||||||
| Investments, amortized cost | € | 26,856 | |||||||||||||
| Investments at fair value | € | € 21,367 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RhDiagnostikTherapieHoldingGmbhMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: RoC Opco LLCFirst Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | 12.17% | |||||||
| Maturity date | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | Feb. 25, 2025 | |||||||
| Principal/Shares | $ 15,918 | |||||||||||||
| Investments, amortized cost | 15,918 | |||||||||||||
| Investments at fair value | $ 15,879 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:RoCOpcoLLCMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Smartronix L L C First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 5.75% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% |
| Interest rate | 10.17% | 6.50% | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | 10.17% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% |
| Maturity date | Nov. 23, 2027 | Jul. 14, 2028 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Nov. 23, 2027 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 | Jul. 14, 2028 |
| Principal/Shares | $ 10,945 | $ 21,000 | ||||||||||||
| Investments, amortized cost | 10,816 | 20,790 | ||||||||||||
| Investments at fair value | $ 10,671 | $ 21,000 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SmartronixMember | bcsf:LightningFincoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Media: Broadcasting & Subscription | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Stanton Carpet Corp. Second Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | |||||||
| Interest rate | 12.75% | 12.75% | 12.75% | 12.75% | 12.75% | 12.75% | 12.75% | |||||||
| Maturity date | Apr. 01, 2028 | Apr. 01, 2028 | Apr. 01, 2028 | Apr. 01, 2028 | Apr. 01, 2028 | Apr. 01, 2028 | Apr. 01, 2028 | |||||||
| Principal/Shares | $ 5,000 | |||||||||||||
| Investments, amortized cost | 4,929 | |||||||||||||
| Investments at fair value | $ 5,000 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:StantonCarpetMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | Second Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Sum Up Holdings Luxembourg S.a.r.l. First Lien Senior Secured Loan Euribor | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | |||||||
| Principal/Shares | € | € 21,000 | |||||||||||||
| Investments, amortized cost | € | 25,038 | |||||||||||||
| Investments at fair value | € | € 23,877 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SumUpHoldingsLuxembourgSarlMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Sumup Holdings Midco S.a.r.l. first Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | Feb. 17, 2026 | |||||||
| Principal/Shares | € | € 30,900 | |||||||||||||
| Investments, amortized cost | € | 35,395 | |||||||||||||
| Investments at fair value | € | € 30,288 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:Sumupholdingsmidcos..r.l.Member | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Surrey Bidco Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 7.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Interest rate | 7.97% | 7.50% | 7.97% | 7.97% | 7.97% | 7.97% | 7.97% | 7.97% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Maturity date | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 | May 11, 2026 |
| Principal/Shares | £ | £ 5,353 | £ 4,979 | ||||||||||||
| Investments, amortized cost | £ | 7,195 | 6,732 | ||||||||||||
| Investments at fair value | £ | £ 5,112 | £ 5,929 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:SurreyBidcoLimitedMember | bcsf:SurreyBidcoLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember | us-gaap:LondonInterbankOfferedRateLiborSwapRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: TGI Sport Bidco Pty Ltd First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Interest rate | 8.50% | 7.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% | 7.50% |
| Maturity date | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 | Apr. 30, 2026 |
| Principal/Shares | $ 9,658 | $ 9,610 | ||||||||||||
| Investments, amortized cost | 6,949 | 6,886 | ||||||||||||
| Investments at fair value | $ 5,841 | $ 6,631 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | T G I Sport Bidco Pty Ltd [Member] | T G I Sport Bidco Pty Ltd [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Utimaco Inc. First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 4.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% |
| Interest rate | 6.58% | 4.10% | 6.58% | 6.58% | 6.58% | 6.58% | 6.58% | 6.58% | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% | 4.10% |
| Maturity date | May 13, 2029 | Aug. 09, 2027 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 | Aug. 09, 2027 |
| Principal/Shares | $ 14,701 | € 8,250 | ||||||||||||
| Investments, amortized cost | 14,701 | 8,328 | ||||||||||||
| Investments at fair value | $ 14,701 | € 8,087 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | bcsf:UtimacoIncMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries [Member] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | London Interbank Offered Rate (LIBOR) [Member] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Utimaco, Inc. First Lien Senior Secured Loan Sofr 1 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | |||||||
| Maturity date | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | |||||||
| Principal/Shares | $ 16,450 | |||||||||||||
| Investments, amortized cost | 16,288 | |||||||||||||
| Investments at fair value | $ 16,450 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Utimaco, Inc. First Lien Senior Secured Loan Sofr 2 | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | |||||||
| Interest rate | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | 8.83% | |||||||
| Maturity date | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | May 13, 2029 | |||||||
| Principal/Shares | $ 8,550 | |||||||||||||
| Investments, amortized cost | 8,466 | |||||||||||||
| Investments at fair value | $ 8,550 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:UtimacoIncMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: V Global Holdings LLCFirst Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 6.00% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 6.50% | 7.00% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% | 7.00% |
| Maturity date | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 |
| Principal/Shares | $ 23,634 | € 9,400 | ||||||||||||
| Investments, amortized cost | 23,634 | 9,466 | ||||||||||||
| Investments at fair value | $ 23,634 | € 9,122 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | V Global Holdings L L C [Member] | V Global Holdings L L C [Member] | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | London Interbank Offered Rate (LIBOR) [Member] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] | London Interbank Offered Rate (LIBOR) [Member] |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: V Global Holdings Llc First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | 5.75% | |||||||
| Interest rate | 8.99% | 8.99% | 8.99% | 8.99% | 8.99% | 8.99% | 8.99% | |||||||
| Maturity date | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | Dec. 22, 2027 | |||||||
| Principal/Shares | $ 23,575 | |||||||||||||
| Investments, amortized cost | 23,575 | |||||||||||||
| Investments at fair value | $ 23,163 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | V Global Holdings L L C [Member] | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | SOFR | |||||||
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: V P A R K BIDCO A B First Lien Senior Secured Loan Two | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% |
| Interest rate | 6.60% | 4.75% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 6.60% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Maturity date | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 |
| Principal/Shares | kr | kr 73,280 | kr 73,280 | ||||||||||||
| Investments, amortized cost | kr | 8,651 | 8,651 | ||||||||||||
| Investments at fair value | kr | kr 6,731 | kr 8,310 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:VPARKBIDCOABMember | bcsf:VPARKBIDCOABMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries [Member] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember | bcsf:NorwegianInterbankOfferedRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: VPARK BIDCO AB First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% | 4.00% |
| Interest rate | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% | 4.75% |
| Maturity date | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 | Mar. 10, 2025 |
| Principal/Shares | kr | kr 56,429 | kr 56,429 | ||||||||||||
| Investments, amortized cost | kr | 9,231 | 9,231 | ||||||||||||
| Investments at fair value | kr | kr 7,438 | kr 8,628 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:VPARKBIDCOABMember | bcsf:VPARKBIDCOABMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries [Member] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] | High Tech Industries [Member] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember | bcsf:CopenhagenInterbankOfferedRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: Zeppelin BidCo Pty Limited First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 5.00% | 6.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 5.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% | 6.00% |
| Interest rate | 7.12% | 5.12% | 7.12% | 7.12% | 7.12% | 7.12% | 7.12% | 7.12% | 5.12% | 5.12% | 5.12% | 5.12% | 5.12% | 5.12% |
| Maturity date | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 | Jun. 28, 2024 |
| Principal/Shares | $ 20,415 | $ 20,415 | ||||||||||||
| Investments, amortized cost | 16,070 | 16,045 | ||||||||||||
| Investments at fair value | $ 13,000 | $ 14,827 | ||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:ZeppelinBidCoPtyLimitedMember | bcsf:ZeppelinBidCoPtyLimitedMember | ||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] |
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember | bcsf:BankBillSwapBidRateMember |
| International Senior Loan Program, LLC | Investment, Identifier [Axis]: iBan First Facility B First Lien Senior Secured Loan | ||||||||||||||
| Investments | ||||||||||||||
| Spread Above Index (as a percent) | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | 8.50% | |||||||
| Interest rate | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | 10.00% | |||||||
| Maturity date | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | Jul. 13, 2028 | |||||||
| Principal/Shares | € | € 10,058 | |||||||||||||
| Investments, amortized cost | € | 11,387 | |||||||||||||
| Investments at fair value | € | € 11,437 | |||||||||||||
| Investment, Issuer Name [Extensible Enumeration] | bcsf:iBanFirstFacilityBMember | |||||||||||||
| Investment, Type [Extensible Enumeration] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | First Lien Senior Secured Loan [Member] | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| Investment, Variable Interest Rate, Type [Extensible Enumeration] | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | bcsf:EuroInterbankOfferRateMember | |||||||
| International Senior Loan Program, LLC | AUD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 43,255 | $ 49,087 | ||||||||||||
| Investments at fair value | $ 37,053 | $ 46,342 | ||||||||||||
| % of Member's Equity | 49.40% | 74.40% | 49.40% | 49.40% | 49.40% | 49.40% | 49.40% | 49.40% | 74.40% | 74.40% | 74.40% | 74.40% | 74.40% | 74.40% |
| International Senior Loan Program, LLC | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 194,001 | £ 115,926 | ||||||||||||
| Investments at fair value | £ | £ 161,936 | £ 113,648 | ||||||||||||
| % of Member's Equity | 215.90% | 182.50% | 215.90% | 215.90% | 215.90% | 215.90% | 215.90% | 215.90% | 182.50% | 182.50% | 182.50% | 182.50% | 182.50% | 182.50% |
| International Senior Loan Program, LLC | CAD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 22,779 | $ 20,453 | ||||||||||||
| Investments at fair value | $ 20,272 | $ 19,970 | ||||||||||||
| % of Member's Equity | 27.00% | 32.00% | 27.00% | 27.00% | 27.00% | 27.00% | 27.00% | 27.00% | 32.00% | 32.00% | 32.00% | 32.00% | 32.00% | 32.00% |
| International Senior Loan Program, LLC | DKK | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | kr | kr 9,231 | kr 9,231 | ||||||||||||
| Investments at fair value | kr | kr 7,438 | kr 8,628 | ||||||||||||
| % of Member's Equity | 9.90% | 13.90% | 9.90% | 9.90% | 9.90% | 9.90% | 9.90% | 9.90% | 13.90% | 13.90% | 13.90% | 13.90% | 13.90% | 13.90% |
| International Senior Loan Program, LLC | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 199,399 | € 149,094 | ||||||||||||
| Investments at fair value | € | € 168,951 | € 143,825 | ||||||||||||
| % of Member's Equity | 225.30% | 231.10% | 225.30% | 225.30% | 225.30% | 225.30% | 225.30% | 225.30% | 231.10% | 231.10% | 231.10% | 231.10% | 231.10% | 231.10% |
| International Senior Loan Program, LLC | NOK | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | kr | kr 8,651 | kr 8,651 | ||||||||||||
| Investments at fair value | kr | kr 6,731 | kr 8,310 | ||||||||||||
| % of Member's Equity | 9.00% | 13.30% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 13.30% | 13.30% | 13.30% | 13.30% | 13.30% | 13.30% |
| International Senior Loan Program, LLC | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 221,334 | $ 160,270 | ||||||||||||
| Investments at fair value | $ 220,636 | $ 160,822 | ||||||||||||
| % of Member's Equity | 294.20% | 258.30% | 294.20% | 294.20% | 294.20% | 294.20% | 294.20% | 294.20% | 258.30% | 258.30% | 258.30% | 258.30% | 258.30% | 258.30% |
| International Senior Loan Program, LLC | Media: Advertising, Printing & Publishing | AUD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 6,949 | $ 6,886 | ||||||||||||
| Investments at fair value | $ 5,841 | $ 6,631 | ||||||||||||
| % of Member's Equity | 7.80% | 10.60% | 7.80% | 7.80% | 7.80% | 7.80% | 7.80% | 7.80% | 10.60% | 10.60% | 10.60% | 10.60% | 10.60% | 10.60% |
| Investment, Industry Sector [Extensible Enumeration] | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | Media: Advertising, Printing & Publishing | |||||||
| International Senior Loan Program, LLC | Aerospace Sector [Member] | AUD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 16,945 | |||||||||||||
| Investments at fair value | $ 15,604 | |||||||||||||
| % of Member's Equity | 20.80% | 20.80% | 20.80% | 20.80% | 20.80% | 20.80% | 20.80% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | Aerospace and Defense Sector [Member] | |||||||
| International Senior Loan Program, LLC | Automotive Sector [Member] | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 24,427 | $ 24,487 | ||||||||||||
| Investments at fair value | $ 24,506 | $ 24,580 | ||||||||||||
| % of Member's Equity | 32.70% | 39.50% | 32.70% | 32.70% | 32.70% | 32.70% | 32.70% | 32.70% | 39.50% | 39.50% | 39.50% | 39.50% | 39.50% | 39.50% |
| Investment, Industry Sector [Extensible Enumeration] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | Automotive Sector [Member] | |||||||
| International Senior Loan Program, LLC | Chemicals, Plastics & Rubber | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 9,466 | |||||||||||||
| Investments at fair value | € | € 9,122 | |||||||||||||
| % of Member's Equity | 12.20% | 12.20% | 12.20% | 12.20% | 12.20% | 12.20% | 12.20% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | |||||||
| International Senior Loan Program, LLC | Chemicals, Plastics & Rubber | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 23,575 | $ 23,634 | ||||||||||||
| Investments at fair value | $ 23,163 | $ 23,634 | ||||||||||||
| % of Member's Equity | 30.90% | 38.00% | 30.90% | 30.90% | 30.90% | 30.90% | 30.90% | 30.90% | 38.00% | 38.00% | 38.00% | 38.00% | 38.00% | 38.00% |
| Investment, Industry Sector [Extensible Enumeration] | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | Chemicals, Plastics & Rubber | |||||||
| International Senior Loan Program, LLC | Consumer Sector, Durable | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 4,929 | |||||||||||||
| Investments at fair value | $ 5,000 | |||||||||||||
| % of Member's Equity | 6.70% | 6.70% | 6.70% | 6.70% | 6.70% | 6.70% | 6.70% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | Consumer Goods Durable Sector [Member] | |||||||
| International Senior Loan Program, LLC | Consumer Sector, Non-Durable | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 15,918 | |||||||||||||
| Investments at fair value | $ 15,879 | |||||||||||||
| % of Member's Equity | 21.20% | 21.20% | 21.20% | 21.20% | 21.20% | 21.20% | 21.20% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | Consumer Goods Non Durable Sector [Member] | |||||||
| International Senior Loan Program, LLC | Fire Finance | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 39,063 | |||||||||||||
| Investments at fair value | £ | £ 36,079 | |||||||||||||
| % of Member's Equity | 48.10% | 48.10% | 48.10% | 48.10% | 48.10% | 48.10% | 48.10% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | Fire Finance | |||||||
| International Senior Loan Program, LLC | Fire Insurance | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 27,908 | € 24,521 | ||||||||||||
| Investments at fair value | € | € 23,818 | € 24,257 | ||||||||||||
| % of Member's Equity | 31.80% | 39.00% | 31.80% | 31.80% | 31.80% | 31.80% | 31.80% | 31.80% | 39.00% | 39.00% | 39.00% | 39.00% | 39.00% | 39.00% |
| Investment, Industry Sector [Extensible Enumeration] | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | Fire Insurance | |||||||
| International Senior Loan Program, LLC | Healthcare and Pharmaceuticals | AUD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 3,291 | $ 3,289 | ||||||||||||
| Investments at fair value | $ 2,608 | $ 3,028 | ||||||||||||
| % of Member's Equity | 3.50% | 4.90% | 3.50% | 3.50% | 3.50% | 3.50% | 3.50% | 3.50% | 4.90% | 4.90% | 4.90% | 4.90% | 4.90% | 4.90% |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | |||||||
| International Senior Loan Program, LLC | Healthcare and Pharmaceuticals | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 16,916 | £ 18,239 | ||||||||||||
| Investments at fair value | £ | £ 13,083 | £ 17,558 | ||||||||||||
| % of Member's Equity | 17.40% | 28.20% | 17.40% | 17.40% | 17.40% | 17.40% | 17.40% | 17.40% | 28.20% | 28.20% | 28.20% | 28.20% | 28.20% | 28.20% |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | Healthcare and Pharmaceuticals | |||||||
| International Senior Loan Program, LLC | Healthcare and Pharmaceuticals | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 57,845 | € 42,510 | ||||||||||||
| Investments at fair value | € | € 47,391 | € 40,071 | ||||||||||||
| % of Member's Equity | 63.20% | 64.40% | 63.20% | 63.20% | 63.20% | 63.20% | 63.20% | 63.20% | 64.40% | 64.40% | 64.40% | 64.40% | 64.40% | 64.40% |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| International Senior Loan Program, LLC | Healthcare and Pharmaceuticals | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 14,068 | $ 14,709 | ||||||||||||
| Investments at fair value | $ 13,347 | $ 14,733 | ||||||||||||
| % of Member's Equity | 17.80% | 23.70% | 17.80% | 17.80% | 17.80% | 17.80% | 17.80% | 17.80% | 23.70% | 23.70% | 23.70% | 23.70% | 23.70% | 23.70% |
| Investment, Industry Sector [Extensible Enumeration] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | Healthcare And Pharmaceuticals [Member] | |||||||
| International Senior Loan Program, LLC | Media: Diversified & Production | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 12,316 | £ 12,255 | ||||||||||||
| Investments at fair value | £ | £ 9,777 | £ 11,782 | ||||||||||||
| % of Member's Equity | 13.00% | 18.90% | 13.00% | 13.00% | 13.00% | 13.00% | 13.00% | 13.00% | 18.90% | 18.90% | 18.90% | 18.90% | 18.90% | 18.90% |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| International Senior Loan Program, LLC | Media: Diversified & Production | CAD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 5,411 | $ 5,701 | ||||||||||||
| Investments at fair value | $ 4,929 | $ 5,682 | ||||||||||||
| % of Member's Equity | 6.50% | 9.10% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 6.50% | 9.10% | 9.10% | 9.10% | 9.10% | 9.10% | 9.10% |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| International Senior Loan Program, LLC | Media: Diversified & Production | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 45,532 | € 45,638 | ||||||||||||
| Investments at fair value | € | € 37,307 | € 44,183 | ||||||||||||
| % of Member's Equity | 49.70% | 71.00% | 49.70% | 49.70% | 49.70% | 49.70% | 49.70% | 49.70% | 71.00% | 71.00% | 71.00% | 71.00% | 71.00% | 71.00% |
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| International Senior Loan Program, LLC | Media: Diversified & Production | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 9,939 | |||||||||||||
| Investments at fair value | $ 9,875 | |||||||||||||
| % of Member's Equity | 13.20% | 13.20% | 13.20% | 13.20% | 13.20% | 13.20% | 13.20% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | Media: Diversified & Production | |||||||
| International Senior Loan Program, LLC | Media: Broadcasting & Subscription | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 2,951 | |||||||||||||
| Investments at fair value | € | € 2,567 | |||||||||||||
| % of Member's Equity | 3.40% | 3.40% | 3.40% | 3.40% | 3.40% | 3.40% | 3.40% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | |||||||
| International Senior Loan Program, LLC | Media: Broadcasting & Subscription | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 23,721 | $ 20,790 | ||||||||||||
| Investments at fair value | $ 23,907 | $ 21,000 | ||||||||||||
| % of Member's Equity | 31.90% | 33.70% | 31.90% | 31.90% | 31.90% | 31.90% | 31.90% | 31.90% | 33.70% | 33.70% | 33.70% | 33.70% | 33.70% | 33.70% |
| Investment, Industry Sector [Extensible Enumeration] | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | Media: Broadcasting & Subscription | |||||||
| International Senior Loan Program, LLC | High Tech Industries | AUD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 22,867 | |||||||||||||
| Investments at fair value | $ 21,856 | |||||||||||||
| % of Member's Equity | 35.10% | 35.10% | 35.10% | 35.10% | 35.10% | 35.10% | 35.10% | |||||||
| International Senior Loan Program, LLC | High Tech Industries | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 7,711 | |||||||||||||
| Investments at fair value | £ | £ 7,581 | |||||||||||||
| % of Member's Equity | 12.20% | 12.20% | 12.20% | 12.20% | 12.20% | 12.20% | 12.20% | |||||||
| International Senior Loan Program, LLC | High Tech Industries | DKK | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | kr | kr 9,231 | kr 9,231 | ||||||||||||
| Investments at fair value | kr | kr 7,438 | kr 8,628 | ||||||||||||
| % of Member's Equity | 9.90% | 13.90% | 9.90% | 9.90% | 9.90% | 9.90% | 9.90% | 9.90% | 13.90% | 13.90% | 13.90% | 13.90% | 13.90% | 13.90% |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| International Senior Loan Program, LLC | High Tech Industries | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 8,328 | |||||||||||||
| Investments at fair value | € | € 8,087 | |||||||||||||
| % of Member's Equity | 10.80% | 10.80% | 10.80% | 10.80% | 10.80% | 10.80% | 10.80% | |||||||
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| International Senior Loan Program, LLC | High Tech Industries | NOK | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | kr | kr 8,651 | kr 8,651 | ||||||||||||
| Investments at fair value | kr | kr 6,731 | kr 8,310 | ||||||||||||
| % of Member's Equity | 9.00% | 13.30% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 9.00% | 13.30% | 13.30% | 13.30% | 13.30% | 13.30% | 13.30% |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| International Senior Loan Program, LLC | High Tech Industries | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 58,858 | $ 53,452 | ||||||||||||
| Investments at fair value | $ 59,104 | $ 53,452 | ||||||||||||
| % of Member's Equity | 78.80% | 85.80% | 78.80% | 78.80% | 78.80% | 78.80% | 78.80% | 78.80% | 85.80% | 85.80% | 85.80% | 85.80% | 85.80% | 85.80% |
| Investment, Industry Sector [Extensible Enumeration] | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | High Tech Industries | |||||||
| International Senior Loan Program, LLC | Retail Sector | CAD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 17,368 | $ 14,752 | ||||||||||||
| Investments at fair value | $ 15,343 | $ 14,288 | ||||||||||||
| % of Member's Equity | 20.50% | 22.90% | 20.50% | 20.50% | 20.50% | 20.50% | 20.50% | 20.50% | 22.90% | 22.90% | 22.90% | 22.90% | 22.90% | 22.90% |
| Investment, Industry Sector [Extensible Enumeration] | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | Retail Sector | |||||||
| International Senior Loan Program, LLC | Services, Business | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 118,511 | £ 70,989 | ||||||||||||
| Investments at fair value | £ | £ 97,885 | £ 70,798 | ||||||||||||
| % of Member's Equity | 130.60% | 113.70% | 130.60% | 130.60% | 130.60% | 130.60% | 130.60% | 130.60% | 113.70% | 113.70% | 113.70% | 113.70% | 113.70% | 113.70% |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| International Senior Loan Program, LLC | Services, Business | EUR | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | € | € 47,369 | € 36,425 | ||||||||||||
| Investments at fair value | € | € 40,659 | € 35,314 | ||||||||||||
| % of Member's Equity | 54.20% | 56.70% | 54.20% | 54.20% | 54.20% | 54.20% | 54.20% | 54.20% | 56.70% | 56.70% | 56.70% | 56.70% | 56.70% | 56.70% |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| International Senior Loan Program, LLC | Services, Business | USD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 45,899 | $ 23,198 | ||||||||||||
| Investments at fair value | $ 45,855 | $ 23,423 | ||||||||||||
| % of Member's Equity | 61.00% | 37.60% | 61.00% | 61.00% | 61.00% | 61.00% | 61.00% | 61.00% | 37.60% | 37.60% | 37.60% | 37.60% | 37.60% | 37.60% |
| Investment, Industry Sector [Extensible Enumeration] | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | Services, Business | |||||||
| International Senior Loan Program, LLC | Services, Consumer [Business] | AUD | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | $ 16,070 | $ 16,045 | ||||||||||||
| Investments at fair value | $ 13,000 | $ 14,827 | ||||||||||||
| % of Member's Equity | 17.30% | 23.80% | 17.30% | 17.30% | 17.30% | 17.30% | 17.30% | 17.30% | 23.80% | 23.80% | 23.80% | 23.80% | 23.80% | 23.80% |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | |||||||
| International Senior Loan Program, LLC | Services, Consumer [Business] | GBP | ||||||||||||||
| Investments | ||||||||||||||
| Investments, amortized cost | £ | £ 7,195 | £ 6,732 | ||||||||||||
| Investments at fair value | £ | £ 5,112 | £ 5,929 | ||||||||||||
| % of Member's Equity | 6.80% | 9.50% | 6.80% | 6.80% | 6.80% | 6.80% | 6.80% | 6.80% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% | 9.50% |
| Investment, Industry Sector [Extensible Enumeration] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | Services, Consumer [Business] | |||||||