Fair Value and Maturity of Debt Outstanding - Schedule of Debt Maturity (Details) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Jun. 30, 2026 |
|---|---|---|
| Debt Instrument [Line Items] | ||
| Total | $ 1,537,158 | $ 1,878,595 |
| 2027 | 406,609 | |
| 2028 | 50,575 | |
| 2029 | 624,428 | |
| 2030 | 27,865 | |
| 2031 | 224,860 | |
| After 5 Years | 202,821 | |
| Credit Facility | Revolving Credit Facility | ||
| Debt Instrument [Line Items] | ||
| Total | 287,152 | 562,328 |
| 2027 | 0 | |
| 2028 | 0 | |
| 2029 | 287,152 | |
| 2030 | 0 | |
| 2031 | 0 | |
| After 5 Years | 0 | |
| Unsecured Debt | Public Notes | ||
| Debt Instrument [Line Items] | ||
| Total | 651,778 | 701,388 |
| 2027 | 263,220 | |
| 2028 | 0 | |
| 2029 | 220,803 | |
| 2030 | 0 | |
| 2031 | 167,755 | |
| After 5 Years | 0 | |
| Unsecured Debt | Prospect Capital InterNotes® | ||
| Debt Instrument [Line Items] | ||
| Total | 598,228 | $ 614,879 |
| 2027 | 143,389 | |
| 2028 | 50,575 | |
| 2029 | 116,473 | |
| 2030 | 27,865 | |
| 2031 | 57,105 | |
| After 5 Years | $ 202,821 |
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- Definition Long-Term Debt, Maturity, After Year Four 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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 second 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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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