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INVESTMENTS - Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Mar. 31, 2024 | [2]
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Investments, Debt and Equity Securities [Abstract] |  |  |
2026 | $ 104,787 |  |
2027 | 133,336 |  |
2028 | 105,409 |  |
2029 | 184,944 |  |
2030 | 159,506 |  |
Thereafter | 0 |  |
Total contractual repayments | 687,982 |  |
Investments in equity securities | 251,084 |  |
Total cost basis of investments held as of March 31, 2025: | $ 939,066 | [1] | $ 854,290
[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.
[2] | Cumulative gross unrealized appreciation for federal income tax purposes is $180.5 million; cumulative gross unrealized depreciation for federal income tax purposes is $115.8 million. Cumulative net unrealized appreciation is $64.7 million, based on a tax cost of $855.8 million.

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