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BORROWINGS - Fair Value (Narrative) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2024 | Mar. 31, 2024
Debt Instrument [Line Items] |  |  |
Fair Value | $ 1,072,230 | $ 920,504 | [1]
Collateral Pledged |  |  |
Debt Instrument [Line Items] |  |  |
Fair Value | $ 847,300 | $ 717,300 |
Credit Facility | Line of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Unused fee percentage | 0.75% | 1.00% |
Credit Facility | Revolving Line of Credit | Line of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, variable rate floor | 0.35% | 0.35% |
[1] | Cumulative gross unrealized appreciation for federal income tax purposes is $180.5 million; cumulative gross unrealized depreciation for federal income tax purposes is $115.8 million. Cumulative net unrealized appreciation is $64.7 million, based on a tax cost of $855.8 million.

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