INVESTMENTS - Schedule of 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]
Fair Value	$ 2,527,537	$ 2,488,715
Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 1,240,745	$ 1,315,630
Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	100.00%	100.00%
Australia \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 25,432	$ 26,291
Australia \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	2.00%	2.00%
Austria \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 5,940	$ 6,026
Austria \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.50%	0.50%
Belgium \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 20,564	$ 20,379
Belgium \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	1.70%	1.50%
Canada \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 1,895	$ 3,998
Canada \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.20%	0.30%
Denmark \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 538	$ 1,082
Denmark \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.00%	0.10%
Finland \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 0	$ 2,207
Finland \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.00%	0.20%
France \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 133,970	$ 137,072
France \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	10.80%	10.40%
Germany \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 49,125	$ 50,672
Germany \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	4.00%	3.90%
Hong Kong \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 14,570	$ 14,162
Hong Kong \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	1.20%	1.10%
Ireland \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 7,248	$ 7,445
Ireland \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.60%	0.60%
Luxembourg \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 1,803	$ 1,839
Luxembourg \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.10%	0.10%
Netherlands \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 41,631	$ 41,260
Netherlands \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	3.40%	3.10%
Panama \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 1,456	$ 1,466
Panama \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.10%	0.10%
Singapore \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 4,990	$ 4,980
Singapore \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.40%	0.40%
Spain \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 4,681	$ 4,777
Spain \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.40%	0.40%
Sweden \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 3,950	$ 4,519
Sweden \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.30%	0.30%
Switzerland \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 585	$ 592
Switzerland \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	0.00%	0.00%
United Kingdom \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 120,445	$ 120,398
United Kingdom \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	9.70%	9.20%
USA \| Jocassee Partners LLC
Schedule of Investments [Line Items]
Fair Value	$ 801,922	$ 866,465
USA \| Jocassee Partners LLC \| Percentage of Total Portfolio, at Fair Value \| Geographic Concentration Risk
Schedule of Investments [Line Items]
Percentage of Total Portfolio	64.60%	65.80%