Annual report pursuant to Section 13 and 15(d)

BORROWINGS - Revolving Line of Credit Narrative (Details)

v3.24.3
BORROWINGS - Revolving Line of Credit Narrative (Details) - Credit Facility - Revolving Line of Credit - Line of Credit
 12 Months Ended
Sep. 30, 2024
USD ($)
obligor
Sep. 30, 2023
USD ($)
Debt Instrument [Line Items]    
Commitment amount $ 293,659,000 $ 223,659,000
Line of credit facility, accordion feature maximum borrowing capacity $ 350,000,000  
Debt instrument, basis spread on variable rate 3.10% 3.10%
Debt instrument, covenant, borrowing base, minimum number of obligors | obligor 25  
Covenant, required minimum net worth of mandatory redeemable term preferred stock $ 325,000,000  
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 $ 418,800,000  
Covenant, senior security, indebtedness, required minimum asset coverage ratio 150.00%  
Senior security, indebtedness, asset coverage amount $ 723,900,000  
Indebtedness asset coverage on our senior securities 243.60%  
Number of obligors | obligor 33  
Secured Overnight Financing Rate (SOFR)    
Debt Instrument [Line Items]    
Debt instrument, basis spread on variable rate 0.10%  
SOFR, Tranche One    
Debt Instrument [Line Items]    
Debt instrument, basis spread on variable rate 3.00%  
SOFR, Thereafter    
Debt Instrument [Line Items]    
Debt instrument, basis spread on variable rate 3.50%