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v3.23.3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2023 USD ($) investment loan | Sep. 30, 2022 USD ($) investment loan | Sep. 30, 2021 USD ($)
Summary of Investment Holdings [Line Items] |  |  |  |  |
Cost | $ 722,269 | [1] | $ 656,053 | [2] |
Fair Value | 704,815 | [1] | 649,615 | [2] |
Total interest income (excluding PIK interest income) | 79,480 |  | 49,759 |  | $ 47,414
PIK interest income | $ 3,550 |  | 4,229 |  | 2,545
Investment company, target percentage of taxable income to distribute to shareholders (up to) | 100.00% |  |  |  |
Edge Adhesives Holdings, Inc. |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Cost | $ 6,100 |  |  |  |
Cost percentage | 0.90% |  |  |  |
Fair Value | $ 2,900 |  |  |  |
Fair value percentage | 0.50% |  |  |  |
OID |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Fair Value | $ 700 |  | $ 900 |  |
Number of loans | loan | 4 |  | 4 |  |
Total interest income (excluding PIK interest income) | $ 200 |  | $ 500 |  | 300
PIK |  |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |  |
Number of investments | investment | 8 |  | 6 |  |
Proceeds from interest received | $ 1,100 |  | $ 2,400 |  | $ 3,400
[1] | Cumulative gross unrealized depreciation for federal income tax purposes is $56.9 million; cumulative gross unrealized appreciation for federal income tax purposes is $33.7 million. Cumulative net unrealized depreciation is $23.2 million, based on a tax cost of $728.0 million.
[2] | Cumulative gross unrealized depreciation for federal income tax purposes is $52.3 million; cumulative gross unrealized appreciation for federal income tax purposes is $35.2 million. Cumulative net unrealized depreciation is $17.1 million, based on a tax cost of $666.7 million.

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