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DISTRIBUTIONS TO COMMON STOCKHOLDERS - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |  |
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Jun. 30, 2025 | Jun. 30, 2024 | Mar. 31, 2025 | Dec. 31, 2024
Equity [Abstract] |  |  |  |
Investment company, cash distributions paid to common stockholders from ordinary income | 50.40% |  |  | 52.90%
Investment company, cash distributions paid to common stockholders from capital gains | 49.60% |  |  | 47.10%
Cash distributions to common stockholders | $ 28.8 | $ 8.8 |  |
Investment company, distributions paid subsequent to fiscal year-end, classified in prior year, ordinary income |  |  | $ 36.7 |
Investment company, distribution paid subsequent to fiscal year-end, classified in prior year, capital gains |  |  | $ 18.7 |
Investment company, net adjustments for tax difference to capital distribution | $ 0.3 | $ 0.2 |  |

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