v3.26.3
Fair Value Measurement - Summary of Changes in Fair Value of Level 3 Assets By Investment (Detail) - Fair Value, Inputs, Level 3 [Member] - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance $ 3,726,694 $ 2,100,629 $ 2,958,691 $ 1,541,927 $ 1,541,927
Net Purchases 1,412,577 [1],[2] 569,609 2,499,541 [1],[3] 1,328,313  
Net Sales, Exits and Repayments (456,578) [1],[4],[5] (73,150) (769,337) [6],[7],[8] (275,233)  
PIK 1,454 542 4,389 1,720  
Accrued Discounts/ Amortized Premiums 2,201 (524) 6,615 2,935  
Net Realized Gain/(Loss) (5,259)   (7,254)    
Net Change in Unrealized Appreciation/ (Depreciation) 1,603 953 (9,953) (1,603)  
Ending Balance 4,682,692 2,598,059 4,682,692 2,598,059 2,958,691
Change in Unrealized Appreciation/ Depreciation (3,340) 1,053 (9,509) (3,242)  
Adjustment of First Lien Senior Secured [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance 3,668,771 2,060,182 2,903,414 1,532,466 1,532,466
Net Purchases 1,373,428 [1],[2] 564,023 2,434,372 [1],[3] 1,292,064  
Net Sales, Exits and Repayments (456,556) [1],[4],[5] (73,137) (745,713) [6],[7],[8] (275,224)  
PIK 1,454 542 4,389 1,720  
Accrued Discounts/ Amortized Premiums 2,187 (524) 6,582 2,931  
Net Realized Gain/(Loss) (4,760)   (4,760)    
Net Change in Unrealized Appreciation/ (Depreciation) 856 926 (12,904) (1,945)  
Ending Balance 4,585,380 2,552,012 4,585,380 2,552,012 2,903,414
Change in Unrealized Appreciation/ Depreciation (3,588) 926 (10,979) (3,588)  
Second Lien Senior Secured [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance   5,484 5,460 4,467 4,467
Net Purchases       1,036  
Net Sales, Exits and Repayments   (13) (5,453) [6],[7],[8] (9)  
Accrued Discounts/ Amortized Premiums     2 4  
Net Change in Unrealized Appreciation/ (Depreciation)   (9) (9) (36)  
Ending Balance 0 5,462 0 5,462 5,460
Change in Unrealized Appreciation/ Depreciation   (9) (0) (31)  
Subordinated Notes [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance   34,963      
Net Purchases   5,586      
Net Change in Unrealized Appreciation/ (Depreciation)   36      
Ending Balance   40,585   40,585  
Change in Unrealized Appreciation/ Depreciation   136      
Collateralized Loan Obligation [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance 57,923   49,318    
Net Purchases [1] 36,272 [2]   62,292 [3]    
Net Sales, Exits and Repayments (22) [1],[4],[5]   (16,687) [6],[7],[8]    
Accrued Discounts/ Amortized Premiums 14   31    
Net Change in Unrealized Appreciation/ (Depreciation) 248   (519)    
Ending Balance 94,435   94,435   49,318
Change in Unrealized Appreciation/ Depreciation 248   (519)    
Preferred Equity [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance 0   499    
Net Sales, Exits and Repayments [6],[7],[8]     (1,484)    
Net Realized Gain/(Loss) (499)   (2,494)    
Net Change in Unrealized Appreciation/ (Depreciation) 499   3,479    
Ending Balance 0   0   499
Change in Unrealized Appreciation/ Depreciation 0   1,989    
Unlisted Common Stock [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Net Purchases [1] 2,877 [2]   2,877 [3]    
Ending Balance $ 2,877   $ 2,877    
CLO Warehouse [Member]          
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]          
Beginning Balance       4,994 $ 4,994
Net Purchases       35,213  
Net Change in Unrealized Appreciation/ (Depreciation)       378  
Ending Balance   $ 40,585   40,585  
Change in Unrealized Appreciation/ Depreciation       $ 377  
[1] Purchases and Sales may include amounts reclassified between investment categories.
[2] Purchases may include investments received in corporate action and restructurings.
[3] Purchases may include investments received in corporate action and restructurings.
[4] Sales may include dividends received and treated as return of capital adjustments for Subordinated Notes and Limited Partnership Interests.
[5] Sales may include investments sold or repaid in corporate action and restructurings.
[6] Purchases and Sales may include amounts reclassified between investment categories.
[7] Sales may include dividends received and treated as return of capital adjustments for Subordinated Notes and Limited Partnership Interests.
[8] Sales may include investments sold or repaid in corporate action and restructurings.