v3.25.3
Fair Value Measurement - Summary of Changes in Fair Value of Level 3 Assets By Investment Type (Details) - USD ($)
$ in Thousands
 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held $ (36,528) $ (92,136)
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Gain (Loss) on Investments Gain (Loss) on Investments
1st Lien/Senior Secured Debt    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held $ (15,988) $ (73,249)
1st Lien/Last-Out Unitranche    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held (2,571) 505
2nd Lien/Senior Secured Debt    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held (929) 6,250
Unsecured Debt    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held 333 (22,094)
Preferred Stock    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held 419 1,619
Common Stock    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held (17,582) (5,284)
Warrants    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Net Change in Unrealized Appreciation (Depreciation) for assets still held (210) 117
Level 3    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 3,431,997 3,343,635
Purchases [1] 734,730 1,000,880
Net Realized Gain (Loss) (120,273) (133,461)
Net Change in Unrealized Appreciation (Depreciation) 79,613 (35,866)
Sales and Settlements [2] (969,607) (801,116)
Net Amortization of Premium/Discount 17,074 19,084
Transfers In [3] 0 12,787
Transfers Out [3] 0 0
Ending Balance 3,173,534 3,405,943
Level 3 | 1st Lien/Senior Secured Debt    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 3,136,683 3,036,965
Purchases [1] 689,005 947,274
Net Realized Gain (Loss) (94,761) (132,482)
Net Change in Unrealized Appreciation (Depreciation) 69,242 (17,908)
Sales and Settlements [2] (840,749) (747,139)
Net Amortization of Premium/Discount 15,633 17,763
Transfers In [3] 0 12,787
Transfers Out [3] 0 0
Ending Balance 2,975,053 3,117,260
Level 3 | 1st Lien/Last-Out Unitranche    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 165,905 144,743
Purchases [1] 28,184 17,744
Net Realized Gain (Loss) (0) (0)
Net Change in Unrealized Appreciation (Depreciation) (22) 505
Sales and Settlements [2] (101,478) (308)
Net Amortization of Premium/Discount 1,216 620
Transfers In [3] 0 0
Transfers Out [3] 0 0
Ending Balance 93,805 163,304
Level 3 | 2nd Lien/Senior Secured Debt    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 46,786 66,562
Purchases [1] 2,229 10,131
Net Realized Gain (Loss) (9,031) (0)
Net Change in Unrealized Appreciation (Depreciation) 8,102 5,293
Sales and Settlements [2] 0 (40,129)
Net Amortization of Premium/Discount (123) 1,028
Transfers In [3] (0) 0
Transfers Out [3] 0 0
Ending Balance 47,963 42,885
Level 3 | Unsecured Debt    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 16,790 27,314
Purchases [1] 221 9,725
Net Realized Gain (Loss) (1,055) (2,025)
Net Change in Unrealized Appreciation (Depreciation) 1,453 (18,373)
Sales and Settlements [2] (9,366) 0
Net Amortization of Premium/Discount 348 (327)
Transfers In [3] 0 (0)
Transfers Out [3] 0 0
Ending Balance 8,391 16,314
Level 3 | Preferred Stock    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 31,246 37,296
Purchases [1] 8,698 112
Net Realized Gain (Loss) 4,717 437
Net Change in Unrealized Appreciation (Depreciation) (2,687) 1,636
Sales and Settlements [2] (15,827) (9,334)
Net Amortization of Premium/Discount 0 (0)
Transfers In [3] 0 (0)
Transfers Out [3] 0 0
Ending Balance 26,147 30,147
Level 3 | Common Stock    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 34,166 30,511
Purchases [1] 6,393 15,894
Net Realized Gain (Loss) (20,143) 609
Net Change in Unrealized Appreciation (Depreciation) 3,735 (7,136)
Sales and Settlements [2] (2,187) (4,206)
Net Amortization of Premium/Discount 0 (0)
Transfers In [3] 0 (0)
Transfers Out [3] 0 0
Ending Balance 21,964 35,672
Level 3 | Warrants    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Beginning Balance 421 244
Purchases [1] 0 0
Net Realized Gain (Loss) (0) 0
Net Change in Unrealized Appreciation (Depreciation) (210) 117
Sales and Settlements [2] 0 0
Net Amortization of Premium/Discount 0 (0)
Transfers In [3] 0 (0)
Transfers Out [3] 0  
Ending Balance $ 211 $ 361
[1] Purchases may include PIK, securities received in corporate actions and restructurings.
[2] Sales and Settlements may include securities delivered in corporate actions and restructuring of investments.
[3] Transfers in (out) of Level 3 are due to a decrease (increase) in the quantity and reliability of broker quotes obtained by the Investment Adviser.