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BORROWINGS - Secured Borrowing Narrative (Details) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
May 31, 2014 | Mar. 31, 2024 | Mar. 31, 2023 | Mar. 31, 2022 | Aug. 31, 2022 | Aug. 31, 2012
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Cost |  | $ 854,290 | [1] | $ 720,630 | [2] |  |  |
Purchase of investments |  | $ 183,924 |  | $ 133,756 |  | $ 92,738 |  |
Secured borrowing liability |  |  |  |  |  | $ 5,100 |  |
Ginsey Home Solutions, Inc. |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |
Cost |  |  |  |  |  |  | $ 12,200 | $ 5,000
Purchase of investments | $ 100 |  |  |  |  |  |  |
[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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