Investments - Geographic Investment (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2026	Dec. 31, 2025
Schedule of Investments [Line Items]
Cost	$ 13,856,590	$ 14,387,967
Fair Value	$ 13,364,295	$ 14,207,294
Fair Value as % of Net Assets	225.00%	227.50%
Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	100.00%	100.00%
United States
Schedule of Investments [Line Items]
Cost	$ 11,852,013	$ 12,488,551
Fair Value	$ 11,369,505	$ 12,259,789
Fair Value as % of Net Assets	191.40%	196.30%
United States \| Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	85.10%	86.30%
Europe
Schedule of Investments [Line Items]
Cost	$ 1,643,362	$ 1,601,031
Fair Value	$ 1,638,203	$ 1,645,999
Fair Value as % of Net Assets	27.60%	26.30%
Europe \| Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	12.30%	11.60%
Bermuda/Cayman Islands
Schedule of Investments [Line Items]
Cost	$ 147,533	$ 148,220
Fair Value	$ 148,236	$ 148,966
Fair Value as % of Net Assets	2.50%	2.40%
Bermuda/Cayman Islands \| Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	1.10%	1.00%
Canada
Schedule of Investments [Line Items]
Cost	$ 151,622	$ 138,265
Fair Value	$ 148,126	$ 140,444
Fair Value as % of Net Assets	2.50%	2.30%
Canada \| Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	1.10%	1.00%
Australia
Schedule of Investments [Line Items]
Cost	$ 50,075
Fair Value	$ 48,048
Fair Value as % of Net Assets	0.80%
Australia \| Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	0.30%
Asia
Schedule of Investments [Line Items]
Cost	$ 11,985	$ 11,900
Fair Value	$ 12,177	$ 12,096
Fair Value as % of Net Assets	0.20%	0.20%
Asia \| Investment Owned, At Fair Value \| Investment Type Concentration Risk
Schedule of Investments [Line Items]
Concentration Risk, Percentage	0.10%	0.10%