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BORROWINGS - Fair Value Narrative (Details) - USD ($) $ in Thousands |  |  | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 30, 2023 | Apr. 10, 2023 | Dec. 31, 2023 | Mar. 31, 2023
Debt Instrument [Line Items] |  |  |  |  |
Fair Value |  |  | $ 902,808 | $ 753,543 | [1]
Collateral Pledged |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Fair Value |  |  | $ 702,900 | $ 639,500 |
Revolving Line of Credit | Line of Credit |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Unused fee percentage |  |  |  | 1.00% |
Credit Facility | Line of Credit |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Unused fee percentage |  |  | 0.50% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | Secured Overnight Financing Rate (SOFR) |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, variable rate floor | 0.35% |  | 0.35% |  |
Debt instrument, basis spread on variable rate |  | 0.11% | 3.25% |  |
Credit Facility | Revolving Line of Credit | Line of Credit | LIBOR |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Debt instrument, variable rate floor |  |  |  | 0.50% |
Debt instrument, basis spread on variable rate |  |  |  | 2.94% |
[1] | Cumulative gross unrealized appreciation for federal income tax purposes is $150.4 million; cumulative gross unrealized depreciation for federal income tax purposes is $119.3 million. Cumulative net unrealized appreciation is $31.1 million, based on a tax cost of $722.4 million.

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