v3.25.2

Taxable/Distributable Income and Dividend Distributions - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Sep. 30, 2024
Investments, Owned, Federal Income Tax Note [Line Items] |  |  |  |  |
Undistributed ordinary income, net |  |  |  |  | $ 696.0
Valuation allowance | $ 6.2 |  | $ 6.2 |  |
Deferred tax assets | 6.5 |  | 6.5 |  |
Investment income, operating, tax expense (benefit), realized and unrealized gains (loss) | 0.1 | $ 0.2 | 0.6 | $ 0.6 |
Unrealized gain (loss), investment and derivative, operating, tax expense (benefit) | $ 0.3 |  | 0.4 |  |
Current income tax |  |  | $ 0.1 |  |
Cost of investments |  |  |  |  | 3,153.0
Unrealized appreciation |  |  |  |  | 674.5
Unrealized depreciation |  |  |  |  | 812.5
Unrealized appreciation (depreciation) |  |  |  |  | 138.0
Short-Term Capital Loss Carryforward |  |  |  |  |
Investments, Owned, Federal Income Tax Note [Line Items] |  |  |  |  |
Undistributed ordinary income, net |  |  |  |  | 73.0
Long-Term Capital Loss Carryforward |  |  |  |  |
Investments, Owned, Federal Income Tax Note [Line Items] |  |  |  |  |
Undistributed ordinary income, net |  |  |  |  | $ 623.0

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