v3.25.2

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
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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