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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Mar. 31, 2023
--- | --- | ---
Summary of Investment Holdings [Line Items] |  |  |  |
Cost | $ 854,290 | [1] | $ 720,630 | [2]
Fair value | 920,504 | [1] | 753,543 | [2]
Edge Adhesives and J.R. Hobbs |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Cost | $ 59,100 |  |  |
Cost percentage | 9.00% |  |  |
Fair value | $ 29,700 |  |  |
Fair value percentage | 4.80% |  |  |
Edge Adhesives Holdings, Inc., J.R. Hobbs Co. and The Mountain |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Cost |  |  | $ 66,900 |
Cost percentage |  |  | 12.00% |
Fair value |  |  | $ 31,700 |
Fair value percentage |  |  | 6.20% |
Non-Control/Non-Affiliate investments |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Investment owned, percent of voting securities | 5.00% |  |  |
Cost | $ 544,799 | [3] | $ 429,305 | [4]
Fair value | 622,233 | [3] | 496,875 | [4]
Affiliate investments |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Cost | 292,082 | [5] | 276,055 | [6]
Fair value | $ 295,366 | [5] | 255,955 | [6]
Affiliate investments | Minimum |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Investment owned, percent of voting securities | 5.00% |  |  |
Affiliate investments | Maximum |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Investment owned, percent of voting securities | 25.00% |  |  |
Control investments |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Investment owned, percent of voting securities | 25.00% |  |  |
Cost | $ 17,409 | [7] | 15,270 | [8]
Fair value | $ 2,905 | [7] | $ 713 | [8]
[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.
[3] | Non-Control/Non-Affiliate investments, as defined by the 1940 Act, are those that are neither Control nor Affiliate investments and in which we own less than 5.0% of the issued and outstanding voting securities.
[4] | Non-Control/Non-Affiliate investments, as defined by the 1940 Act, are those that are neither Control nor Affiliate investments and in which we own less than 5.0% of the issued and outstanding voting securities.
[5] | Affiliate investments, as defined by the 1940 Act, are those that are not Control investments and in which we own, with the power to vote, between and inclusive of 5.0% and 25.0% of the issued and outstanding voting securities.
[6] | Affiliate investments, as defined by the 1940 Act, are those that are not Control investments and in which we own, with the power to vote, between and inclusive of 5.0% and 25.0% of the issued and outstanding voting securities.
[7] | Control investments, as defined by the 1940 Act, are those where we have the power to exercise a controlling influence over the management or policies of the portfolio company, which may include owning, with the power to vote, more than 25.0% of the issued and outstanding voting securities.
[8] | Control investments, as defined by the 1940 Act, are those where we have the power to exercise a controlling influence over the management or policies of the portfolio company, which may include owning, with the power to vote, more than 25.0% of the issued and outstanding voting securities.

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