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INVESTMENTS - Narrative (Details) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2024 USD ($) portfolioCompany state industry | Jul. 31, 2024 USD ($) | May 31, 2024 USD ($) | Sep. 30, 2024 USD ($) portfolioCompany state industry | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) portfolioCompany state industry | Sep. 30, 2023 USD ($) | Mar. 31, 2024 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |  |  |  |  |
Principal repayments of investments |  |  |  |  |  | $ 28,000 | $ 0 |  |
Purchase of investments |  |  |  |  |  | 20,098 | 114,788 |  |
Success fee income |  |  |  | $ 150 | $ 0 | $ 1,703 | $ 0 |  |
Number of investment portfolio company | portfolioCompany | 22 |  |  | 22 |  | 22 |  |  |
Number of states which have invested in the company location | state | 18 |  |  | 18 |  | 18 |  |  |
Number of industries that have made investments | industry | 15 |  |  | 15 |  | 15 |  |  |
Fair Value | $ 853,307 |  |  | $ 853,307 |  | $ 853,307 |  | $ 920,504 | [1]
Uncollectible receivables allowance, minimum required day for uncollectible adjustment |  |  |  |  |  | 90 days |  |  |
Gross receivables from portfolio companies | 2,100 |  |  | 2,100 |  | $ 2,100 |  | 2,200 |
Allowance for uncollectible receivables | 1,600 |  |  | 1,600 |  | 1,600 |  | $ 1,400 |
Five Largest Portfolio Investments | Investment Portfolio Benchmark | Customer Concentration Risk |  |  |  |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |  |  |  |
Fair Value | 402,600 |  |  | $ 402,600 |  | $ 402,600 |  |  |
Percentage of Total Investments |  |  |  |  |  | 47.20% |  |  |
Funko Acquisition Holdings, LLC |  |  |  |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |  |  |  |
Principal repayments of investments |  |  | $ 21 |  |  |  |  |  |
Realized gain on preferred equity |  |  | $ 2 |  |  |  |  |  |
Nocturne Villa Rentals, Inc. |  |  |  |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |  |  |  |
Purchase of investments |  | $ 18,500 |  |  |  |  |  |  |
Nth Degree Investment Group, LLC |  |  |  |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |  |  |  |
Principal repayments of investments | 25,000 |  |  |  |  |  |  |  |
Realized gain on preferred equity | 42,300 |  |  |  |  |  |  |  |
Success fee income | $ 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.

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