v3.26.1
INVESTMENTS - Jocassee Partners LLC (Details) - USD ($)
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
May 08, 2019
May 07, 2019
Schedule of Investments [Line Items]              
Committed investment amount $ 413,217,000   $ 413,217,000   $ 400,635,000    
Total dividend income 14,021,000 $ 14,593,000 25,926,000 $ 25,335,000      
Fair Value 2,458,590,000   2,458,590,000   2,398,524,000    
Cost 2,500,365,000   2,500,365,000   2,424,280,000    
Borrowings under credit facility 277,226,000   277,226,000   226,786,000    
Repayments received / sales of portfolio investments     342,290,000 274,620,000      
Jocassee Partners LLC              
Schedule of Investments [Line Items]              
Repayments received / sales of portfolio investments     1,355,500,000   1,303,700,000    
Loss on sale of investments 100,000   100,000        
Due from related parties 700,000   700,000   52,000,000.0    
Jocassee Partners LLC | Subscription Facility | Bank Of America Subscription Facility | Line of Credit              
Schedule of Investments [Line Items]              
Borrowings under credit facility 180,800,000   180,800,000   182,900,000    
Jocassee Partners LLC | Subscription Facility | Citibank N.A. Subscription Facility | Line of Credit              
Schedule of Investments [Line Items]              
Borrowings under credit facility 299,200,000   299,200,000   328,500,000    
Jocassee Partners LLC | Subscription Facility | Term Debt Securitization | Line of Credit              
Schedule of Investments [Line Items]              
Borrowings under credit facility 324,100,000   324,100,000   323,900,000    
Jocassee Partners LLC              
Schedule of Investments [Line Items]              
Dividends 31,400,000 15,700,000 62,800,000 31,400,000      
Total dividend income 2,900,000 $ 1,400,000 5,700,000 $ 2,900,000      
Fair Value 1,126,044,000   1,126,044,000   1,241,387,000    
Cost 1,186,491,000   $ 1,186,491,000   $ 1,290,521,000    
Interest-earning assets, average yield     8.10%   8.30%    
Jocassee Partners LLC | Long-Term Investments              
Schedule of Investments [Line Items]              
Fair Value 1,126,000,000   $ 1,126,000,000   $ 1,241,400,000    
Cost $ 1,186,500,000   $ 1,186,500,000   $ 1,290,500,000    
Jocassee Partners LLC | SCRS              
Schedule of Investments [Line Items]              
Committed investment amount           $ 500,000,000.0 $ 100,000,000.0