v3.26.3
INVESTMENTS - Valuation Inputs (Details)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
USD ($)
investment
Sep. 30, 2025
USD ($)
Sep. 30, 2026
USD ($)
investment
Sep. 30, 2025
USD ($)
Dec. 31, 2025
USD ($)
investment
Schedule of Investments [Line Items]          
Fair value $ 2,509,771   $ 2,509,771   $ 2,398,524
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]     Net unrealized appreciation (depreciation) on investments Net unrealized appreciation (depreciation) on investments  
Unrealized gain (loss)     $ (28,400) $ 19,800  
Total investments funded 195,965 $ 148,773 566,791 554,731  
Senior debt and 1st lien notes          
Schedule of Investments [Line Items]          
Fair value 1,771,736   1,771,736   1,676,334
Subordinated debt and 2nd lien notes          
Schedule of Investments [Line Items]          
Fair value 233,332   233,332   190,290
Equity shares          
Schedule of Investments [Line Items]          
Fair value $ 444,996   444,996   $ 436,466
Investments with No Previous Contractual Commitment to Provide Financing          
Schedule of Investments [Line Items]          
Total investments funded     435,400 464,500  
Investment with Previous Commitment to Provide Financing          
Schedule of Investments [Line Items]          
Total investments funded     $ 131,400    
Investment, Excluding Short Term Investment, with Previous Commitment to Provide Financing          
Schedule of Investments [Line Items]          
Total investments funded       $ 90,200  
Yield Analysis | Senior debt and 1st lien notes | Market Approach          
Schedule of Investments [Line Items]          
Number of investments | investment 6   6   7
Fair value $ 49,600   $ 49,600   $ 31,700
Yield Analysis | Subordinated debt and 2nd lien notes | Market Approach          
Schedule of Investments [Line Items]          
Number of investments | investment 1   1    
Fair value $ 600   $ 600    
Yield Analysis | Equity shares | Black-Scholes          
Schedule of Investments [Line Items]          
Number of investments | investment 1   1    
Fair value $ 400   $ 400    
Market Approach | Senior debt and 1st lien notes | Yield Analysis          
Schedule of Investments [Line Items]          
Number of investments | investment         2
Fair value         $ 5,800
Market Approach | Subordinated debt and 2nd lien notes | Expected Recovery          
Schedule of Investments [Line Items]          
Number of investments | investment 1   1    
Fair value $ 8,500   $ 8,500    
Net Asset Approach | Equity shares | Yield Analysis          
Schedule of Investments [Line Items]          
Number of investments | investment 1   1    
Fair value $ 4,200   $ 4,200    
Valuation, Unadjusted Prices From Independent Pricing Services And Independent Indicative Broker Quotes | Debt securities, structured product position | Yield Analysis          
Schedule of Investments [Line Items]          
Number of investments | investment 1   1    
Fair value $ 10,000   $ 10,000