Fair Value of Financial Instruments - Reconciliation of Liabilities Measured at Fair Value Using Significant Unobservable Inputs Level 3 (Details) - 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] | ||
| Net realized (gain) loss | $ 31,304 | $ 8,355 |
| Level 3 | Long-Term Credit Facility | ||
| Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] | ||
| Beginning balance (cost - $683,855 and $443,855, respectively) | 683,837 | 443,880 |
| Net change in unrealized (depreciation) appreciation included in earnings | (27) | (15) |
| Borrowings | 341,500 | 260,000 |
| Repayments | (707,000) | (405,000) |
| Ending balance (cost - $318,355 and $298,855, respectively) | $ 318,310 | $ 298,865 |
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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 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 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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- Definition Amount of realized gain (loss) on investment. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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