Fair Value of Financial Instruments - Reconciliation of Liabilities Measured at Fair Value Using Significant Unobservable Inputs Level 3 (Details) - Level 3 - Long-Term Credit Facility - USD ($) $ in Thousands |
6 Months Ended | |||
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Mar. 31, 2026 |
Mar. 31, 2025 |
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| Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] | ||||
| Beginning balance | $ 425,477 | $ 460,361 | ||
| Net change in unrealized appreciation (depreciation) included in earnings | (997) | (1,949) | ||
| Borrowings | [1] | 70,000 | 80,000 | |
| Repayments | [1] | (305,000) | (227,000) | |
| Transfers in and/or out of Level 3 | 0 | 0 | ||
| Ending Balance Before Temporary Draws | 189,480 | 311,412 | ||
| Ending balance | 199,480 | 311,412 | ||
| Temporary draws outstanding, at cost | $ 10,000 | $ 0 | ||
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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability net change in unrealized depreciation appreciation included in earnings. No definition available.
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- Definition Fair value measurement with unobservable inputs reconciliation recurring basis liability temporary draws outstanding. No definition available.
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- Definition Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value Before Temporary Draws No definition available.
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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 purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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