v3.26.1
Fair Value - Summary of Changes in Fair Value of Level 3 Assets and Liabilities (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Opening balance $ 2,076,418 $ 1,956,286
Net realized gain (loss) (14) 22
Net change in unrealized gain (loss) $ (416) $ (1,163)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net Change In Unrealized Gain Loss On Investments Net Change In Unrealized Gain Loss On Investments
Purchase of investment securities $ 126,471 [1] $ 196,788 [2]
Proceeds from dispositions of investment securities (137,366) (196,288)
Transfers in/out of Level 3 0 0
Closing balance 2,065,093 1,955,645
Net change in unrealized gain (loss) $ (416) $ 1,375
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Net Change In Unrealized Gain Loss On Investments Net Change In Unrealized Gain Loss On Investments
Senior Secured Loans [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Opening balance $ 1,260,389 $ 1,117,118
Net realized gain (loss) (14) 30
Net change in unrealized gain (loss) (6,589) (2,905)
Purchase of investment securities 110,953 [1] 188,200 [2]
Proceeds from dispositions of investment securities (125,410) (185,838)
Transfers in/out of Level 3 0 0
Closing balance 1,239,329 1,116,605
Net change in unrealized gain (loss) (6,589) (367)
Equipment Financing [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Opening balance 119,021 181,016
Net realized gain (loss) 0 (8)
Net change in unrealized gain (loss) 1,017 (6,493)
Purchase of investment securities 3,487 [1] 2,734 [2]
Proceeds from dispositions of investment securities (11,956) (10,450)
Transfers in/out of Level 3 0 0
Closing balance 111,569 166,799
Net change in unrealized gain (loss) 1,017 (6,493)
Preferred Equity [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Opening balance 32,858 31,682
Net realized gain (loss) 0 0
Net change in unrealized gain (loss) (126) (113)
Purchase of investment securities 844 [1] 770 [2]
Proceeds from dispositions of investment securities 0 0
Transfers in/out of Level 3 0 0
Closing balance 33,576 32,339
Net change in unrealized gain (loss) (126) (113)
Common Equity/Equity Interests/Warrants [Member]    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]    
Opening balance 664,150 626,470
Net realized gain (loss) 0 0
Net change in unrealized gain (loss) 5,282 8,348
Purchase of investment securities 11,187 [1] 5,084 [2]
Proceeds from dispositions of investment securities 0 0
Transfers in/out of Level 3 0 0
Closing balance 680,619 639,902
Net change in unrealized gain (loss) $ 5,282 $ 8,348
[1] Includes PIK capitalization and accretion of discount.
[2] Includes PIK capitalization and accretion of discount