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 |
9 Months Ended | |||||
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Jun. 30, 2026 |
Jun. 30, 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 | (723) | 1,023 | ||||
| Borrowings | [1] | 250,000 | 97,000 | |||
| Repayments | [1] | (375,000) | (242,000) | |||
| Transfers in and/or out of Level 3 | 0 | 0 | ||||
| Ending Balance Before Temporary Draws | 299,754 | 316,384 | ||||
| Temporary draws outstanding, at cost | 10,000 | 0 | ||||
| Ending balance | [2] | $ 309,755 | $ 316,384 | |||
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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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