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DISTRIBUTIONS TO COMMON STOCKHOLDERS - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2024
Equity [Abstract] |  |  |  |  |
Investment company, cash distributions paid to common stockholders from ordinary income | 52.90% | 53.20% | 52.90% | 53.20% |
Investment company, cash distributions paid to common stockholders from capital gains | 47.10% | 46.80% | 47.10% | 46.80% |
Cash distributions to common stockholders |  |  | $ 52.1 | $ 52.1 |
Payments of dividends |  |  | 67.4 | 67.4 |
Investment company, distributions paid subsequent to fiscal year-end, classified in prior year, ordinary income |  |  |  |  | $ 18.7
Investment company, distribution paid subsequent to fiscal year-end, classified in prior year, capital gains |  |  |  |  | $ 1.4
Investment company, net adjustments for tax difference to capital distribution | $ 0.4 | $ 0.4 | $ 1.2 | $ 0.4 |

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