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v3.25.2

BORROWINGS - Revolving Credit Facility Narrative (Details) - Credit Facility - Line of Credit - Revolving Line of Credit | 9 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2025 USD ($) obligor | Sep. 30, 2024 USD ($)
Debt Instrument [Line Items] |  |
Line of credit facility, maximum borrowing capacity | $ 320,000,000 | $ 293,659,000
Line of credit facility, accordion feature maximum borrowing capacity | $ 400,000,000 |
Debt instrument, basis spread on variable rate | 2.60% | 3.10%
Debt instrument, covenant, borrowing base, minimum number of obligors | obligor | 25 |
Covenant, required minimum net worth of mandatory redeemable term preferred stock | $ 500,000,000.0 |
Covenant, required minimum net worth of mandatory redeemable term preferred stock, plus percent of all equity and subordinated debt raised | 50.00% |
Covenant, required minimum net worth of mandatory redeemable term preferred stock, minus percent of any equity or subordinated debt redeemed or retired | 50.00% |
Covenant, required minimum net worth of mandatory redeemable term preferred stock, plus percent of all equity and subordinated debt raised, minus percent of any equity or subordinated debt redeemed or retired | $ 500,000,000.0 |
Debt instrument, covenant, senior security, indebtedness, required minimum asset coverage ratio | 150.00% |
Senior security, indebtedness, asset coverage amount | $ 727,000,000.0 |
Indebtedness asset coverage on our senior securities | 267.90% |
Investment company, number of obligor | obligor | 33 |
Secured Overnight Financing Rate (SOFR), Tranche One |  |
Debt Instrument [Line Items] |  |
Debt instrument, basis spread on variable rate | 2.60% |
Secured Overnight Financing Rate (SOFR), Thereafter |  |
Debt Instrument [Line Items] |  |
Debt instrument, basis spread on variable rate | 3.10% |

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