v3.26.1
Related Party Transactions - Schedule of Fees and Expenses Accrued Under the Investment Advisory Agreement (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Related Party Transaction [Line Items]      
Base Management Fee $ 48.0 $ 52.0  
Subordinated Incentive Fee on Income [1] 25.0 39.0  
Administrative Services Expenses 1.0 1.0  
Management fees payable 48.0   $ 50.0
Subordinated income incentive fees payable [2] 25.0   $ 28.0
FS/KKR Advisor, LLC      
Related Party Transaction [Line Items]      
Base Management Fee 48.0 52.0  
Subordinated Incentive Fee on Income 25.0 39.0  
Administrative Services Expenses 2.0 3.0  
Base management fees 50.0 53.0  
Management fees payable 48.0    
Incentive fee paid 28.0 35.0  
Subordinated income incentive fees payable 25.0    
Allocation of costs of administrative personnel for services rendered 2.0 2.0  
Broken deal cost 0.1    
Payment for administrative services expenses $ 1.0 $ 1.0  
[1] See Note 2 and 4 for a discussion of the methodology employed by the Company in calculating the subordinated income incentive fees.
[2] See Note 2 and 4 for a discussion of the methodology employed by the Company in calculating the subordinated income incentive fees.