Realized Gains or Losses and Net Unrealized Appreciation or Depreciation - Narrative (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Jun. 30, 2025 |
Mar. 31, 2025 |
Dec. 31, 2024 |
Jun. 30, 2024 |
Mar. 31, 2024 |
Dec. 31, 2023 |
Jun. 30, 2025 |
Jun. 30, 2024 |
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| Schedule of Investments [Line Items] | ||||||||
| Net unrealized appreciation (depreciation) | $ (18,572) | $ 82,023 | $ 19,614 | $ (26,199) | $ 25,252 | $ 25,025 | $ 83,100 | $ 24,100 |
| Investments in debt securities | ||||||||
| Schedule of Investments [Line Items] | ||||||||
| Net unrealized appreciation (depreciation) | (1,500) | (38,600) | 88,600 | 49,600 | ||||
| Foreign currency forward contracts | ||||||||
| Schedule of Investments [Line Items] | ||||||||
| Net unrealized appreciation (depreciation) | (1,900) | (1,100) | 2,300 | 4,500 | ||||
| Investments in equity securities | ||||||||
| Schedule of Investments [Line Items] | ||||||||
| Net unrealized appreciation (depreciation) | (14,200) | (19,900) | 13,800 | 30,500 | ||||
| Exited Investments | ||||||||
| Schedule of Investments [Line Items] | ||||||||
| Net unrealized appreciation (depreciation) | $ (900) | $ (83,600) | $ (21,600) | $ (60,500) | ||||
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- Definition Amount, before tax, of unrealized gain (loss) on investment in debt and equity securities and foreign currency transaction on investment in debt and equity securities from change in market price, classified as operating. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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