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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands | 3 Months Ended |
--- | --- | ---
Dec. 31, 2023 USD ($) investment loan | Dec. 31, 2022 USD ($) | Sep. 30, 2023 USD ($) loan investment
Schedule of Investments [Line Items] |  |  |  |
Cost | $ 759,634 |  | $ 722,269 | [1]
Fair Value | 749,985 |  | $ 704,815 | [1]
Total interest income (excluding PIK interest income) | 21,588 | $ 17,369 |  |
PIK interest income | 1,408 | 998 |  |
OID |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Fair Value | $ 700 |  |  |
Number of loans | loan | 4 |  | 4 |
Total interest income (excluding PIK interest income) | $ 52 | 49 |  |
PIK |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Number of investments | investment | 10 |  | 8 |
Proceeds from interest received | $ 0 | $ 400 |  |
Edge Adhesives Holdings Inc |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Cost | $ 6,100 |  | $ 6,100 |
Cost percentage | 0.90% |  | 0.90% |
Fair Value | $ 2,800 |  | $ 2,900 |
Fair value percentage | 0.40% |  | 0.50% |
[1] | Investment was exited subsequent to December 31, 2023. Refer to Note 12 – Subsequent Events in the accompanying Notes to the Consolidated Financial Statements for additional information.

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