Proceeds From Issuance of Unsecured Debt, Net

No definition available.

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- Definition

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.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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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Weighted average interest rate of debt outstanding.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

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Prospect Capital InterNotes® - Narrative (Details) - USD ($)	12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024	Feb. 06, 2026	Feb. 13, 2020
Debt Instrument [Line Items]
Outstanding amount	$ 1,878,595,000	$ 2,103,554,000
Net gain (loss) on extinguishment of debt	4,219,000	972,000	$ (248,000)
Prospect Capital InterNotes®
Debt Instrument [Line Items]
Proceeds from issuance of discounts and offering costs	29,799,000	151,592,000	156,840,000
Repayments of unsecured debt	62,152,000	8,388,000	10,917,000
Unsecured Debt \| Prospect Capital InterNotes®
Debt Instrument [Line Items]
Outstanding amount	614,879,000	647,232,000
Proceeds from issuance of discounts and offering costs	29,799,000	151,592,000
Net proceeds of issuance of debt	$ 29,392,000	$ 149,431,000
Weighted average interest rate	6.85%	7.15%
Net gain (loss) on extinguishment of debt	$ (319,000)	$ (168,000)
Interest expense	37,562,000	35,386,000	$ 19,075,000
Unsecured Debt \| Prospect Capital InterNotes® \| Survivor’s Option
Debt Instrument [Line Items]
Repayments of unsecured debt		$ 6,889,000
Unsecured Debt \| Prospect Capital InterNotes® \| Survivor’s Option \| In Accordance With Survivor’s Option
Debt Instrument [Line Items]
Repayments of unsecured debt	$ 11,025,000
Unsecured Debt \| Prospect Capital InterNotes® \| Survivor’s Option \| With Weighted Average Interest Rate
Debt Instrument [Line Items]
Weighted average interest rate	6.41%
Repayments of unsecured debt	$ 20,658,000
Unsecured Debt \| Prospect Capital InterNotes® \| Maximum
Debt Instrument [Line Items]
Face amount				$ 1,000,000,000	$ 1,000,000,000
Stated rate	8.00%	8.00%
Unsecured Debt \| Prospect Capital InterNotes® \| Minimum
Debt Instrument [Line Items]
Stated rate	6.25%	6.50%