INVESTMENTS - Schedules of Geographic Composition of Investments at Cost and Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Schedule of Investments [Line Items]
Cost	$ 633,269	$ 516,168
Fair Value	$ 626,799	$ 512,036
Fair Value as % of Net Assets	131.69%	144.30%
Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	100.00%	100.00%
USA
Schedule of Investments [Line Items]
Cost	$ 604,891	$ 496,774
Fair Value	$ 598,331	$ 492,518
Fair Value as % of Net Assets	125.71%	138.80%
USA | Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	95.45%	96.19%
Canada
Schedule of Investments [Line Items]
Cost	$ 11,794	$ 6,374
Fair Value	$ 11,818	$ 6,376
Fair Value as % of Net Assets	2.48%	1.80%
Canada | Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	1.89%	1.25%
United Kingdom
Schedule of Investments [Line Items]
Cost	$ 7,614	$ 9,045
Fair Value	$ 7,665	$ 9,139
Fair Value as % of Net Assets	1.61%	2.58%
United Kingdom | Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	1.22%	1.78%
Ireland
Schedule of Investments [Line Items]
Cost	$ 1,743	$ 1,741
Fair Value	$ 1,741	$ 1,750
Fair Value as % of Net Assets	0.37%	0.49%
Ireland | Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	0.28%	0.34%
Luxembourg
Schedule of Investments [Line Items]
Cost	$ 5,665	$ 1,255
Fair Value	$ 5,683	$ 1,255
Fair Value as % of Net Assets	1.19%	0.35%
Luxembourg | Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	0.91%	0.25%
Netherlands
Schedule of Investments [Line Items]
Cost	$ 1,562	$ 979
Fair Value	$ 1,561	$ 998
Fair Value as % of Net Assets	0.33%	0.28%
Netherlands | Investments at Fair Value | Investment Type Concentration Risk
Schedule of Investments [Line Items]
% of Fair Value	0.25%	0.19%