Summary of Significant Accounting Policies (Policies)	6 Months Ended
Jun. 30, 2023
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation: The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, for interim financial information and with the instructions for Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. For a more complete discussion of significant accounting policies and certain other information, the Company’s interim unaudited consolidated financial statements should be read in conjunction with its audited consolidated financial statements as of and for the year ended December 31, 2022 included in the Company’s annual report on Form 10-K for the year ended December 31, 2022. Operating results for the six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The December 31, 2022 consolidated balance sheet and consolidated schedule of investments are derived from the Company’s audited consolidated financial statements as of and for the year ended December 31, 2022. The Company is considered an investment company under GAAP and follows the accounting and reporting guidance applicable to investment companies under Financial Accounting Standards Board, or the FASB, Accounting Standards Codification Topic 946, Financial Services—Investment Companies.
Use of Estimates	Use of Estimates: The preparation of the unaudited consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Capital Gains Incentive Fee	Capital Gains Incentive Fee: Pursuant to the terms of the investment advisory agreement, the incentive fee on capital gains is determined and payable in arrears as of the end of each calendar year (or upon termination of the investment advisory agreement). This fee equals 20.0% of the Company’s incentive fee capital gains, which shall equal the realized capital gains of Corporate Capital Trust, Inc., or CCT, (as predecessor-by-merger to the Company), FS KKR Capital Corp. II, or FSKR, (as predecessor-by-merger to the Company) and the Company (without duplication) on a cumulative basis from inception, calculated as of the end of each calendar year, computed net of all realized capital losses and unrealized capital depreciation (without duplication) on a cumulative basis, less the aggregate amount of any capital gain incentive fees previously paid by CCT, FSKR and the Company. On a quarterly basis, the Company accrues for the capital gains incentive fee by calculating such fee as if it were due and payable as of the end of such period. The Company includes unrealized gains in the calculation of the capital gains incentive fee expense and related accrued capital gains incentive fee. This accrual reflects the incentive fees that would be payable to the Advisor if the Company’s entire portfolio was liquidated at its fair value as of the balance sheet date even though the Advisor is not entitled to an incentive fee with respect to unrealized gains unless and until such gains are actually realized.
Subordinated Income Incentive Fee	Subordinated Income Incentive Fee: Pursuant to the terms of the investment advisory agreement, the Advisor may also be entitled to receive a subordinated incentive fee on income. The subordinated incentive fee on income under the investment advisory agreement, which is calculated and payable quarterly in arrears, equals 17.5% of the Company’s “pre-incentive fee net investment income” for the immediately preceding quarter and is subject to a hurdle rate, expressed as a rate of return on the value of the Company’s net assets, equal to 1.75% per quarter, or an annualized hurdle rate of 7.0%. As a result, the Advisor will not earn this incentive fee for any quarter until the Company’s pre-incentive fee net investment income for such quarter exceeds the hurdle rate of 1.75%. Once the Company’s pre-incentive fee net investment income in any quarter exceeds the hurdle rate, the Advisor will be entitled to a “catch-up” fee equal to the amount of the pre-incentive fee net investment income in excess of the hurdle rate, until the Company’s pre-incentive fee net investment income for such quarter equals 2.12%, or 8.48% annually, of net assets. Thereafter, the Advisor will be entitled to receive 17.5% of pre-incentive fee net investment income.
Reclassifications	Reclassifications: Certain amounts in the unaudited consolidated financial statements as of and for the three and six months ended June 30, 2022 and the audited consolidated financial statements as of and for the year ended December 31, 2022 may have been reclassified to conform to the classifications used to prepare the unaudited consolidated financial statements as of and for the three and six months ended June 30, 2023.
Revenue Recognition	Revenue Recognition: Security transactions are accounted for on the trade date. The Company records interest income on an accrual basis to the extent that it expects to collect such amounts. The Company records dividend income on the ex-dividend date. Distributions received from limited liability company ("LLC") and limited partnership ("LP") investments are evaluated to determine if the distribution should be recorded as dividend income or a return of capital. The Company does not accrue as a receivable interest or dividends on loans and securities if it has reason to doubt its ability to collect such income. The Company's policy is to place investments on non-accrual status when there is reasonable doubt that interest income will be collected. The Company considers many factors relevant to an investment when placing it on or removing it from non-accrual status including, but not limited to, the delinquency status of the investment, economic and business conditions, the overall financial condition of the underlying investment, the value of the underlying collateral, bankruptcy status, if any, and any other facts or circumstances relevant to the investment. If there is reasonable doubt that the Company will receive any previously accrued interest, then the accrued interest will be written-off. Payments received on non-accrual investments may be recognized as income or applied to principal depending upon the collectability of the remaining principal and interest. Non-accrual investments may be restored to accrual status when principal and interest become current and are likely to remain current based on the Company's judgment. Loan origination fees, original issue discount and market discount are capitalized and the Company amortizes such amounts as interest income over the respective term of the loan or security. Upon the prepayment of a loan or security, any unamortized loan origination fees and original issue discount are recorded as interest income. Structuring and other non-recurring upfront fees are recorded as fee income when earned. For the six months ended June 30, 2023 and 2022, the Company recognized $6 and $16, respectively, in structuring fee revenue. The Company records prepayment premiums on loans and securities as fee income when it receives such amounts.
Derivative Instruments	Derivative Instruments: The Company's derivative instruments include foreign currency forward contracts and cross currency swaps. The Company recognizes all derivative instruments as assets or liabilities at fair value in its consolidated financial statements. Derivative contracts entered into by the Company are not designated as hedging instruments, and as a result, the Company presents changes in fair value through net change in unrealized appreciation (depreciation) on derivative instruments in the consolidated statements of operations. Realized gains and losses of the derivative instruments are included in net realized gains (losses) on derivative instruments in the consolidated statements of operations.
Recent Accounting Pronouncements	Recent Accounting Pronouncements: In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848),” which provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments apply only to contracts, hedging relationships, and other transactions that reference London Interbank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued because of reference rate reform. In January 2021, the FASB issued ASU No. 2021-01, Reference Rate Reform (Topic 848), which expanded the scope of Topic 848 to include derivative instruments impacted by discounting transition. ASU 2020-04 and ASU 2021-01 are effective for all entities through December 31, 2022. The expedients and exceptions provided by the amendments do not apply to contract modifications and hedging relationships entered into or evaluated after December 31, 2022, except for hedging transactions as of December 31, 2022, that an entity has elected certain optional expedients for and that are retained through the end of the hedging relationship. In December 2022, the FASB issued ASU No. 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, which deferred the sunset day of this guidance to December 31, 2024. The Company is currently evaluating the impact of the adoption of ASU 2020-04 and 2021-01 on its consolidated financial statements.
Fair Value Measurement	Under existing accounting guidance, fair value is defined as the price that the Company would receive upon selling an investment or pay to transfer a liability in an orderly transaction to a market participant in the principal or most advantageous market for the investment. This accounting guidance emphasizes valuation techniques that maximize the use of observable market inputs and minimize the use of unobservable inputs. Inputs refer broadly to the assumptions that market participants would use in pricing an asset or liability, including assumptions about risk. Inputs may be observable or unobservable. Observable inputs are inputs that reflect the assumptions market participants would use in pricing an asset or liability developed based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the assumptions market participants would use in pricing an asset or liability developed based on the best information available in the circumstances. The Company classifies the inputs used to measure these fair values into the following hierarchy as defined by current accounting guidance: Level 1: Inputs that are quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2: Inputs that are quoted prices for similar assets or liabilities in active markets. Level 3: Inputs that are unobservable for an asset or liability. A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Summary of Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2023

Basis of Presentation: The accompanying unaudited consolidated financial statements of the Company have been prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, for interim financial information and with the instructions for Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. For a more complete discussion of significant accounting policies and certain other information, the Company’s interim unaudited consolidated financial statements should be read in conjunction with its audited consolidated financial statements as of and for the year ended December 31, 2022 included in the Company’s annual report on Form 10-K for the year ended December 31, 2022. Operating results for the six months ended June 30, 2023 are not necessarily indicative of the results that may be expected for the year ending December 31, 2023. The December 31, 2022 consolidated balance sheet and consolidated schedule of investments are derived from the Company’s audited consolidated financial statements as of and for the year ended December 31, 2022. The Company is considered an investment company under GAAP and follows the accounting and reporting guidance applicable to investment companies under Financial Accounting Standards Board, or the FASB, Accounting Standards Codification Topic 946, Financial Services—Investment Companies.

Use of Estimates

Use of Estimates: The preparation of the unaudited consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Capital Gains Incentive Fee

Capital Gains Incentive Fee: Pursuant to the terms of the investment advisory agreement, the incentive fee on capital gains is determined and payable in arrears as of the end of each calendar year (or upon termination of the investment advisory agreement). This fee equals 20.0% of the Company’s incentive fee capital gains, which shall equal the realized capital gains of Corporate Capital Trust, Inc., or CCT, (as predecessor-by-merger to the Company), FS KKR Capital Corp. II, or FSKR, (as predecessor-by-merger to the Company) and the Company (without duplication) on a cumulative basis from inception, calculated as of the end of each calendar year, computed net of all realized capital losses and unrealized capital depreciation (without duplication) on a cumulative basis, less the aggregate amount of any capital gain incentive fees previously paid by CCT, FSKR and the Company. On a quarterly basis, the Company accrues for the capital gains incentive fee by calculating such fee as if it were due and payable as of the end of such period.

The Company includes unrealized gains in the calculation of the capital gains incentive fee expense and related accrued capital gains incentive fee. This accrual reflects the incentive fees that would be payable to the Advisor if the Company’s entire portfolio was liquidated at its fair value as of the balance sheet date even though the Advisor is not entitled to an incentive fee with respect to unrealized gains unless and until such gains are actually realized.

Subordinated Income Incentive Fee

Subordinated Income Incentive Fee: Pursuant to the terms of the investment advisory agreement, the Advisor may also be entitled to receive a subordinated incentive fee on income. The subordinated incentive fee on income under the investment advisory agreement, which is calculated and payable quarterly in arrears, equals 17.5% of the Company’s “pre-incentive fee net investment income” for the immediately preceding quarter and is subject to a hurdle rate, expressed as a rate of return on the value of the Company’s net assets, equal to 1.75% per quarter, or an annualized hurdle rate of 7.0%. As a result, the Advisor will not earn this incentive fee for any quarter until the Company’s pre-incentive fee net investment income for such quarter exceeds the hurdle rate of 1.75%. Once the Company’s pre-incentive fee net investment income in any quarter exceeds the hurdle rate, the Advisor will be entitled to a “catch-up” fee equal to the amount of the pre-incentive fee net investment income in excess of the hurdle rate, until the Company’s pre-incentive fee net investment income for such quarter equals 2.12%, or 8.48% annually, of net assets. Thereafter, the Advisor will be entitled to receive 17.5% of pre-incentive fee net investment income.

Reclassifications

Reclassifications: Certain amounts in the unaudited consolidated financial statements as of and for the three and six months ended June 30, 2022 and the audited consolidated financial statements as of and for the year ended December 31, 2022 may have been reclassified to conform to the classifications used to prepare the unaudited consolidated financial statements as of and for the three and six months ended June 30, 2023.

Revenue Recognition

Revenue Recognition: Security transactions are accounted for on the trade date. The Company records interest income on an accrual basis to the extent that it expects to collect such amounts. The Company records dividend income on the ex-dividend date. Distributions received from limited liability company ("LLC") and limited partnership ("LP") investments are evaluated to determine if the distribution should be recorded as dividend income or a return of capital. The Company does not accrue as a receivable interest or dividends on loans and securities if it has reason to doubt its ability to collect such income. The Company's policy is to place investments on non-accrual status when there is reasonable doubt that interest income will be collected. The Company considers many factors relevant to an investment when placing it on or removing it from non-accrual status including, but not limited to, the delinquency status of the investment, economic and business conditions, the overall financial condition of the underlying investment, the value of the underlying collateral, bankruptcy status, if any, and any other facts or circumstances relevant to the investment. If there is reasonable doubt that the Company will receive any previously accrued interest, then the accrued interest will be written-off. Payments received on non-accrual investments may be recognized as income or applied to principal depending upon the collectability of the remaining principal and interest. Non-accrual investments may be restored to accrual status when principal and interest become current and are likely to remain current based on the Company's judgment. Loan origination fees, original issue discount and market discount are capitalized and the Company amortizes such amounts as interest income over the respective term of the loan or security. Upon the prepayment of a loan or security, any unamortized loan origination fees and original issue discount are recorded as interest income. Structuring and other non-recurring upfront fees are recorded as fee income when earned. For the six months ended June 30, 2023 and 2022, the Company recognized $6 and $16, respectively, in structuring fee revenue. The Company records prepayment premiums on loans and securities as fee income when it receives such amounts.

Derivative Instruments

Derivative Instruments: The Company's derivative instruments include foreign currency forward contracts and cross currency swaps. The Company recognizes all derivative instruments as assets or liabilities at fair value in its consolidated financial statements. Derivative contracts entered into by the Company are not designated as hedging instruments, and as a result, the Company presents changes in fair value through net change in unrealized appreciation (depreciation) on derivative instruments in the consolidated statements of operations. Realized gains and losses of the derivative instruments are included in net realized gains (losses) on derivative instruments in the consolidated statements of operations.

Recent Accounting Pronouncements

Recent Accounting Pronouncements: In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848),” which provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships, and other transactions affected by reference rate reform if certain criteria are met. The amendments apply only to contracts, hedging relationships, and other transactions that reference London Interbank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued because of reference rate reform. In January 2021, the FASB issued ASU No. 2021-01, Reference Rate Reform (Topic 848), which expanded the scope of Topic 848 to include derivative instruments impacted by discounting transition. ASU 2020-04 and ASU 2021-01 are effective for all entities through December 31, 2022. The expedients and exceptions provided by the amendments do not apply to contract modifications and hedging relationships entered into or evaluated after December 31, 2022, except for hedging transactions as of December 31, 2022, that an entity has elected certain optional expedients for and that are retained through the end of the hedging relationship. In December 2022, the FASB issued ASU No. 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, which deferred the sunset day of this guidance to December 31, 2024. The Company is currently evaluating the impact of the adoption of ASU 2020-04 and 2021-01 on its consolidated financial statements.

Fair Value Measurement

Under existing accounting guidance, fair value is defined as the price that the Company would receive upon selling an investment or pay to transfer a liability in an orderly transaction to a market participant in the principal or most advantageous market for the investment. This accounting guidance emphasizes valuation techniques that maximize the use of observable market inputs and minimize the use of unobservable inputs. Inputs refer broadly to the assumptions that market participants would use in pricing an asset or liability, including assumptions about risk. Inputs may be observable or unobservable. Observable inputs are inputs that reflect the assumptions market participants would use in pricing an asset or liability developed based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the assumptions market participants would use in pricing an asset or liability developed based on the best information available in the circumstances. The Company classifies the inputs used to measure these fair values into the following hierarchy as defined by current accounting guidance:

Level 1: Inputs that are quoted prices (unadjusted) in active markets for identical assets or liabilities.

Level 2: Inputs that are quoted prices for similar assets or liabilities in active markets.

Level 3: Inputs that are unobservable for an asset or liability.

A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.