v3.26.1
Related Party Transactions - Schedule of Fees and Expenses Accrued Under the Investment Advisory Agreement (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Related Party Transaction [Line Items]          
Base Management Fee $ 44.0 $ 53.0 $ 92.0 $ 105.0  
Subordinated Income Incentive Fee 23.0 36.0 48.0 75.0  
Administrative Services Expenses 1.0 1.0 2.0 2.0  
Management fees payable 44.0   44.0   $ 50.0
Subordinated income incentive fees payable 12.0   12.0   $ 28.0
FS/KKR Advisor, LLC          
Related Party Transaction [Line Items]          
Base Management Fee 44.0 53.0 92.0 105.0  
Subordinated Income Incentive Fee 12.0 36.0 37.0 75.0  
Administrative Services Expenses 3.0 $ 2.0 5.0 5.0  
Base management fees     98.0 105.0  
Management fees payable 44.0   $ 44.0    
Incentive fee waived     50.00%    
Investment company, incentive fee waived     $ 11.0    
Incentive fee paid     53.0 74.0  
Subordinated income incentive fees payable $ 12.0   12.0    
Allocation of costs of administrative personnel for services rendered     4.0 4.0  
Broken deal cost     0.2    
Payment for administrative services expenses     $ 3.0 $ 2.0