Fair Value and Maturity of Debt Outstanding - Schedule of Debt Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022
Debt Instrument [Line Items]
Total	$ 2,670,175	$ 2,769,156
Remainder of 2023	283,872
2024	81,902
2025	157,667
2026	430,293
2027	375,176
After 5 Years	1,341,265
Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Total	799,851	839,464
Remainder of 2023	0
2024	0
2025	0
2026
2027	0
After 5 Years	799,851
Convertible Notes
Debt Instrument [Line Items]
Total	156,168	216,669
Remainder of 2023	0
2024	0
2025	156,168
2026	0
2027	0
After 5 Years	0
Unsecured Debt \| Public Notes
Debt Instrument [Line Items]
Total	1,365,112	1,365,459
Remainder of 2023	283,872
2024	81,240
2025	0
2026	400,000
2027	300,000
After 5 Years	300,000
Unsecured Debt \| Prospect Capital InterNotes
Debt Instrument [Line Items]
Total	349,044	$ 347,564
Remainder of 2023	0
2024	662
2025	1,499
2026	30,293
2027	75,176
After 5 Years	$ 241,414

Long-Term Debt, Maturity, After Year Four

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in remainder of current fiscal year.

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