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RELATED PARTY TRANSACTIONS - Schedule of Related Party Transactions (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Related Party Transactions [Abstract] |  |  |  |
Average total assets subject to base management fee |  | $ 794,857 | $ 777,657 | $ 685,600
Multiplied by annual base management fee of 1.75% |  | 1.75% | 1.75% | 1.75%
Base management fee | [1] | $ 13,910 | $ 13,609 | $ 11,998
Portfolio company fee credit |  | (5,593) | (2,866) | (3,263)
Syndicated loan fee credit |  | (37) | (101) | (126)
Net Base Management Fee |  | 8,280 | 10,642 | 8,609
Loan servicing fee | [1] | 8,888 | 8,862 | 8,053
Credits to base management fee – loan servicing fee | [1] | (8,888) | (8,862) | (8,053)
Net Loan Servicing Fee |  | 0 | 0 | 0
Incentive fee | [1] | 10,486 | 11,410 | 10,255
Incentive fee credit |  | (2,344) | (204) | 0
Net Incentive Fee |  | 8,142 | 11,206 | 10,255
Credits to fees from Adviser - other | [1] | $ (7,974) | $ (3,171) | $ (3,389)
Base management fee |  | 1.75% | 1.75% | 1.75%
[1] | Refer to Note 4—Related Party Transactions for additional information.

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