Annual report [Section 13 and 15(d), not S-K Item 405]

BORROWINGS - Schedule of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details)

v3.25.3
BORROWINGS - Schedule of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($)
$ in Thousands
 12 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Debt Instrument [Line Items]    
Credit Facility $ 0 $ 70,600
Significant Unobservable Inputs (Level 3) | Fair Value, Recurring    
Debt Instrument [Line Items]    
Credit Facility 0 70,600
Significant Unobservable Inputs (Level 3) | Fair Value, Recurring | Long-Term Debt    
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]    
Beginning balance 70,600 47,800
Borrowings 332,000 221,200
Repayments (402,600) (198,400)
Net unrealized (appreciation) depreciation 0 0
Ending balance $ 0 $ 70,600