v3.25.4
Investments - Rollforward of Level 3 Investments Measured at Fair Value (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Fair value, beginning balance $ 359,897 $ 400,195
Funding and purchases of investments, at cost 155,740 132,478
Principal payments and sale proceeds received from investments (145,740) (158,714)
Transfers between investments 0 1
Gross transfers out of Level 3 0 0
Fair value, ending balance $ 359,400 $ 359,897
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net change in unrealized gains/( losses) on investments Net change in unrealized gains/( losses) on investments
Net change in unrealized (losses) on Level 3 investments held $ (6,387) $ (8,931)
Amortization and accretion of premiums and discounts, net and end-of term payments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ 5,475 $ 3,160
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Interest income from investments Interest expense and amortization of fees
Net realized losses on investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ (25,598) $ (14,549)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net realized losses on investments Net realized losses on investments
Net change in unrealized losses included in earnings    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ 4,316 $ (6,173)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net change in unrealized gains/( losses) on investments Net change in unrealized gains/( losses) on investments
Payment-in-kind coupon    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ 5,310 $ 3,499
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Interest income from investments Interest income from investments
Debt investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Fair value, beginning balance $ 318,838 $ 375,025
Funding and purchases of investments, at cost 149,132 125,804
Principal payments and sale proceeds received from investments (143,736) (157,579)
Transfers between investments (1,616) (4,788)
Gross transfers out of Level 3 0 0
Fair value, ending balance 302,379 318,838
Net change in unrealized (losses) on Level 3 investments held (14,755) (14,449)
Debt investments | Amortization and accretion of premiums and discounts, net and end-of term payments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 5,475 3,160
Debt investments | Net realized losses on investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (25,121) (14,231)
Debt investments | Net change in unrealized losses included in earnings    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (5,903) (12,052)
Debt investments | Payment-in-kind coupon    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 5,310 3,499
Warrant investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Fair value, beginning balance 24,111 16,915
Funding and purchases of investments, at cost 3,773 2,855
Principal payments and sale proceeds received from investments (1,852) (1,135)
Transfers between investments (634) (26)
Gross transfers out of Level 3 0 0
Fair value, ending balance 30,287 24,111
Net change in unrealized (losses) on Level 3 investments held 3,700 5,409
Warrant investments | Amortization and accretion of premiums and discounts, net and end-of term payments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 0 0
Warrant investments | Net realized losses on investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (124) (268)
Warrant investments | Net change in unrealized losses included in earnings    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 5,013 5,770
Warrant investments | Payment-in-kind coupon    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 0 0
Equity investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Fair value, beginning balance 16,948 8,255
Funding and purchases of investments, at cost 2,835 3,819
Principal payments and sale proceeds received from investments (152) 0
Transfers between investments 2,250 4,815
Gross transfers out of Level 3 0 0
Fair value, ending balance 26,734 16,948
Net change in unrealized (losses) on Level 3 investments held 4,668 109
Equity investments | Amortization and accretion of premiums and discounts, net and end-of term payments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 0 0
Equity investments | Net realized losses on investments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings (353) (50)
Equity investments | Net change in unrealized losses included in earnings    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings 5,206 109
Equity investments | Payment-in-kind coupon    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Gain (loss) included in earnings $ 0 $ 0