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INVESTMENTS - Investments Classified by Contractual Maturity Date (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Mar. 31, 2023 | [2]
--- | --- | --- | ---
Investments, Debt and Equity Securities [Abstract] |  |  |
2025 | $ 72,770 |  |
2026 | 236,193 |  |
2027 | 185,776 |  |
2028 | 38,250 |  |
2029 | 100,394 |  |
Thereafter | 25,000 |  |
Total contractual repayments | 658,383 |  |
Investments in equity securities | 195,907 |  |
Total cost basis of investments held as of March 31, 2024: | $ 854,290 | [1] | $ 720,630
[1] | 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.
[2] | Cumulative gross unrealized appreciation for federal income tax purposes is $150.4 million; cumulative gross unrealized depreciation for federal income tax purposes is $119.3 million. Cumulative net unrealized appreciation is $31.1 million, based on a tax cost of $722.4 million.

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