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v3.25.3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Apr. 04, 2024 | Sep. 30, 2025 USD ($) segment investment loan | Sep. 30, 2024 USD ($) loan investment | Sep. 30, 2023 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |  |
Reverse stock split, conversion ratio | 0.5 |  |  |  |  |
Cost |  | $ 876,614 | [1] | $ 771,011 | [2] |
Fair Value |  | 859,124 | [1] | 796,260 | [2] |
Total interest income (excluding PIK interest income) |  | 82,291 |  | 87,618 |  | $ 79,480
PIK interest income |  | $ 4,990 |  | 5,676 |  | 3,550
Investment company, target percentage of taxable income to distribute to shareholders (up to) |  | 100.00% |  |  |  |
Number of reporting segments | segment |  | 1 |  |  |  |
OID |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |
Fair Value |  | $ 200 |  | $ 600 |  |
Number of loans | loan |  | 2 |  | 2 |  |
Total interest income (excluding PIK interest income) |  | $ 400 |  | $ 400 |  | 200
PIK |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |
Number of investments | investment |  | 9 |  | 8 |  |
Proceeds from interest received |  | $ 7,200 |  | $ 200 |  | $ 1,100
B+T Group Acquisition, Inc., Edge Adhesives Holdings, Inc,. And WB Xcel Holdings, LLC |  |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |  |
Cost |  | $ 28,800 |  | $ 28,300 |  |
Cost percentage |  | 3.60% |  | 4.10% |  |
Fair Value |  | $ 13,000 |  | $ 12,800 |  |
Fair value percentage |  | 1.70% |  | 1.90% |  |
[1] | Cumulative gross unrealized depreciation for federal income tax purposes is $59.7 million; cumulative gross unrealized appreciation for federal income tax purposes is $34.1 million. Cumulative net unrealized depreciation is $25.5 million, based on a tax cost of $884.7 million.
[2] | Cumulative gross unrealized depreciation for federal income tax purposes is $66.1 million; cumulative gross unrealized appreciation for federal income tax purposes is $85.8 million. Cumulative net unrealized appreciation is $19.7 million, based on a tax cost of $776.5 million

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