SIGNIFICANT SUBSIDIARIES - Summarized Financial Information Operation Statement (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Investment Company, Nonconsolidated Subsidiary [Line Items]
Net investment income	$ 19,425	$ 14,444	$ 12,438	$ 11,899	$ 9,726	$ 9,043	$ 46,307	$ 30,668
Net unrealized depreciation (appreciation) on investments	(5,390)	$ 3,649	$ (12,248)	(2,054)	$ (691)	$ 7,051	(13,989)	4,306
I-45 SLF LLC
Investment Company, Nonconsolidated Subsidiary [Line Items]
Total revenues	4,648			3,114			12,217	9,262
Total expenses	(2,195)			(1,023)			(5,253)	(3,041)
Net investment income	2,453			2,091			6,964	6,221
Net unrealized depreciation (appreciation) on investments	(4,031)			(2,405)			(12,522)	(3,603)
Net realized (losses) gains	(29)			58			42	231
Net (decrease) increase in members’ equity resulting from operations	$ (1,607)			$ (256)			$ (5,516)	$ 2,849