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DISTRIBUTIONS TO COMMON STOCKHOLDERS - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023
Equity [Abstract] |  |  |  |  |
Investment company, cash distributions paid to common stockholders from ordinary income |  |  |  | 52.90% | 53.20%
Investment company, cash distributions paid to common stockholders from capital gains |  |  |  | 47.10% | 46.80%
Cash distributions to common stockholders | $ 61,000 | $ 76,100 | $ 47,000 |  |
Undistributed ordinary income | 36,673 | 18,708 | 21,400 |  |
Undistributed capital gain | $ 18,663 | $ 1,373 | $ 10,600 |  |
Investment company, deemed distribution approach, notice period | 60 days |  |  |  |

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