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BORROWINGS - Fair Value Narrative (Details) - USD ($) $ in Thousands |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
May 13, 2022 | Mar. 31, 2023 | Sep. 30, 2022
Debt Instrument [Line Items] |  |  |
Fair Value |  | $ 678,759 | $ 649,615
Collateral Pledged |  |  |
Debt Instrument [Line Items] |  |  |
Fair Value |  | $ 572,200 | $ 577,600
Credit Facility | Line of Credit | Revolving Line of Credit |  |  |
Debt Instrument [Line Items] |  |  |
Unused fee percentage | 0.35% | 0.75% | 0.50%
Credit Facility | Line of Credit | Revolving Line of Credit | SOFR |  |  |
Debt Instrument [Line Items] |  |  |
Debt instrument, basis spread on variable rate |  | 3.00% | 2.81%

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