INVESTMENTS - Schedules of Portfolio Composition by Geographic Composition of Investments at Cost and Fair Value (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Schedule of Investments [Line Items]
Amortized Cost	$ 2,075,365	$ 1,666,169
Fair Value	$ 2,046,887	$ 1,641,686
Fair Value as % of Net Assets	206.62%	219.51%
Investment Owned at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Total Investments at Fair Value	100.00%	100.00%
United States
Schedule of Investments [Line Items]
Amortized Cost	$ 1,996,273	$ 1,613,815
Fair Value	$ 1,967,950	$ 1,589,384
Fair Value as % of Net Assets	198.66%	212.52%
United States | Investment Owned at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Total Investments at Fair Value	96.14%	96.82%
Canada
Schedule of Investments [Line Items]
Amortized Cost	$ 43,552	$ 38,462
Fair Value	$ 43,604	$ 38,292
Fair Value as % of Net Assets	4.40%	5.12%
Canada | Investment Owned at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Total Investments at Fair Value	2.13%	2.33%
Germany
Schedule of Investments [Line Items]
Amortized Cost	$ 22,192
Fair Value	$ 22,139
Fair Value as % of Net Assets	2.23%
Germany | Investment Owned at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Total Investments at Fair Value	1.08%
United Kingdom
Schedule of Investments [Line Items]
Amortized Cost	$ 13,348	$ 13,892
Fair Value	$ 13,194	$ 14,010
Fair Value as % of Net Assets	1.33%	1.87%
United Kingdom | Investment Owned at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Total Investments at Fair Value	0.65%	0.85%