INVESTMENTS - Geographic Composition Of Investment At Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Schedule of Investments [Line Items]
Total investments at fair value	$ 1,363,048	$ 1,349,121
Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 143,697	$ 146,477
Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	100.00%	100.00%
Australia | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 4,360	$ 4,449
Australia | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	3.00%	3.00%
Belgium | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 7,577	$ 7,531
Belgium | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	5.30%	5.10%
Canada | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 1,847	$ 2,221
Canada | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	1.30%	1.50%
France | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 27,948	$ 28,669
France | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	19.40%	19.60%
Germany | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 7,120	$ 7,277
Germany | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	5.00%	5.00%
Hong Kong | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 6,179	$ 6,033
Hong Kong | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	4.30%	4.10%
Netherlands | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 9,182	$ 9,193
Netherlands | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	6.40%	6.30%
New Zealand | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 2,462	$ 2,596
New Zealand | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	1.70%	1.80%
Singapore | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 3,989	$ 3,984
Singapore | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	2.80%	2.70%
United Kingdom | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 20,282	$ 20,401
United Kingdom | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	14.10%	13.90%
USA | Banff Partners LP
Schedule of Investments [Line Items]
Total investments at fair value	$ 52,751	$ 54,123
USA | Banff Partners LP | Investment Owned, At Fair Value | Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	36.70%	37.00%