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INVESTMENTS - Schedule of Investment Principal Repayments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Mar. 31, 2025 | [1]
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Investments, Debt and Equity Securities [Abstract] |  |
Remainder of fiscal year | $ 15,000 |
2027 | 61,186 |
2028 | 120,282 |
2029 | 269,844 |
2030 | 159,506 |
Thereafter | 111,680 |
Total contractual repayments | 737,498 |
Investments in equity securities | 299,702 |
Total cost basis of investments held as of September 30, 2025: | $ 1,037,200 | $ 939,066
[1] | Cumulative gross unrealized appreciation for federal income tax purposes is $183.3 million; cumulative gross unrealized depreciation for federal income tax purposes is $144.9 million. Cumulative net unrealized appreciation is $38.5 million, based on a tax cost of $940.9 million.

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