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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Mar. 31, 2023
--- | --- | ---
Summary of Investment Holdings [Line Items] |  |  |
Cost | $ 868,504 | $ 720,630 | [1]
Fair Value | 902,808 | 753,543 | [1]
J.R. Hobbs Co. and The Mountain Corporation |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Cost | $ 66,900 |  |
Cost percentage | 10.00% |  |
Fair Value | $ 30,900 |  |
Fair value percentage | 5.00% |  |
J.R. Hobbs, The Mountain and SFEG Holdings, Inc. |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Cost |  | $ 66,900 |
Cost percentage |  | 12.00% |
Fair Value |  | $ 31,700 |
Fair value percentage |  | 6.20% |
[1] | 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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