v3.26.1
Investments - Schedule of Investments and Cash and Cash Equivalents (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Sep. 30, 2025
Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments $ 1,222,322 $ 1,236,888
Cash and Cash Equivalents, Cost Value 44,858 51,739
Total investments and cash and cash equivalents 1,267,180 1,288,627
Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 1,203,513 1,287,273
Cash and Cash Equivalents, Cost Value 44,807 51,783
Total investments and cash and cash equivalents 1,248,320 1,339,056
First Lien | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 509,412 606,949
First Lien | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 481,700 582,373
US Government Securities [Member] | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 209,462 124,809
US Government Securities [Member] | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 209,427 124,788
Second Lien | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 15,232 18,619
Second Lien | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 14,825 18,161
Subordinated Debt / Corporate Notes | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 66,337 60,575
Subordinated Debt / Corporate Notes | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 66,788 60,933
Subordinated Notes in PSLF | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 140,287 140,287
Subordinated Notes in PSLF | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 140,288 140,287
Equity | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 199,234 203,291
Equity | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 236,578 293,218
Equity in PSLF | Cost    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments 82,358 82,358
Equity in PSLF | Fair Value    
Schedule Of Investment Income Reported Amounts By Category [Line Items]    
Total investments $ 53,907 $ 67,513