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DISTRIBUTIONS TO COMMON STOCKHOLDERS - Investment Company, Changes in Net Assets (Details) - USD ($) $ in Thousands | 12 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Underdistributed (overdistributed) net investment income |  |
Investment Company, Changes in Net Assets [Line Items] |  |
Increase (decrease) due to reclassifications of permanent differences | $ 9,623 | $ 1,695
Accumulated net realized gain in excess of distributions |  |
Investment Company, Changes in Net Assets [Line Items] |  |
Increase (decrease) due to reclassifications of permanent differences | (8,424) | (881)
Capital in excess of par value |  |
Investment Company, Changes in Net Assets [Line Items] |  |
Increase (decrease) due to reclassifications of permanent differences | $ (1,199) | $ (814)

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