Investments - Schedule of Fair Value Portfolio of Investments by Asset Class (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2026	Dec. 31, 2025
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 4,845,903	$ 4,466,647
Warrants
Schedule Of Investments [Line Items]
Investments at Fair Value	46,290	41,162
Investment Type Concentration Risk \| Total Investments Benchmark
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 4,845,903	$ 4,466,647
Percentage of Total Portfolio	100.00%	100.00%
Investment Type Concentration Risk \| Total Investments Benchmark \| Senior Secured Debt
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 4,568,831	$ 4,209,798
Percentage of Total Portfolio	94.30%	94.20%
Investment Type Concentration Risk \| Total Investments Benchmark \| Unsecured Debt
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 77,146	$ 69,614
Percentage of Total Portfolio	1.60%	1.60%
Investment Type Concentration Risk \| Total Investments Benchmark \| Preferred Stock
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 57,771	$ 52,735
Percentage of Total Portfolio	1.20%	1.20%
Investment Type Concentration Risk \| Total Investments Benchmark \| Common Stock
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 89,063	$ 86,275
Percentage of Total Portfolio	1.80%	1.90%
Investment Type Concentration Risk \| Total Investments Benchmark \| Warrants
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 46,290	$ 41,162
Percentage of Total Portfolio	1.00%	0.90%
Investment Type Concentration Risk \| Total Investments Benchmark \| Investment Funds & Vehicles
Schedule Of Investments [Line Items]
Investments at Fair Value	$ 6,802	$ 7,063
Percentage of Total Portfolio	0.10%	0.20%