Prospect Capital InterNotes® - Schedule Issued Notes (Details) - Prospect Capital InterNotes® - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2026	Sep. 30, 2025
Debt Instrument [Line Items]
Principal Amount	$ 805	$ 7,868
Unsecured Debt
Debt Instrument [Line Items]
Principal Amount	$ 805	$ 7,868
Weighted Average Interest Rate	6.30%	7.42%
Unsecured Debt \| Minimum
Debt Instrument [Line Items]
Interest Rate Range	6.00%	6.25%
Unsecured Debt \| Maximum
Debt Instrument [Line Items]
Interest Rate Range	6.75%	8.00%
Unsecured Debt \| Maturity Date Range One
Debt Instrument [Line Items]
Tenor at Origination (in years)	3 years	3 years
Principal Amount	$ 426	$ 4,213
Weighted Average Interest Rate	6.05%	7.18%
Unsecured Debt \| Maturity Date Range One \| Minimum
Debt Instrument [Line Items]
Interest Rate Range	6.00%	6.25%
Unsecured Debt \| Maturity Date Range One \| Maximum
Debt Instrument [Line Items]
Interest Rate Range	6.25%	7.50%
Unsecured Debt \| Maturity Date Range Two
Debt Instrument [Line Items]
Tenor at Origination (in years)	5 years	5 years
Principal Amount	$ 121	$ 1,076
Weighted Average Interest Rate	6.34%	7.61%
Unsecured Debt \| Maturity Date Range Two \| Minimum
Debt Instrument [Line Items]
Interest Rate Range	6.25%	6.50%
Unsecured Debt \| Maturity Date Range Two \| Maximum
Debt Instrument [Line Items]
Interest Rate Range	6.50%	7.75%
Unsecured Debt \| Maturity Date Range Three
Debt Instrument [Line Items]
Tenor at Origination (in years)	7 years	7 years
Principal Amount	$ 258	$ 2,579
Weighted Average Interest Rate	6.69%	7.72%
Unsecured Debt \| Maturity Date Range Three \| Minimum
Debt Instrument [Line Items]
Interest Rate Range	6.50%	6.75%
Unsecured Debt \| Maturity Date Range Three \| Maximum
Debt Instrument [Line Items]
Interest Rate Range	6.75%	8.00%

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

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