Investments - SLP Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Investment Income
Total investment income	$ 62,815	$ 49,545	$ 161,190	$ 145,864
Expenses
Interest and debt financing expenses	14,381	12,265	36,051	37,115
Total expenses	28,712	27,784	78,669	89,370
Net investment income (loss)	34,103	21,761	82,521	65,850
Net realized and unrealized gain (losses)
Total net gains (losses)	(23,052)	1,581	(20,560)	31,678
Net increase (decrease) in members' equity resulting from operations	11,051	$ 23,342	61,961	$ 97,528
Bain Capital Senior Loan Program, LLC
Investment Income
Interest Income	10,202		20,013
Total investment income	10,202		20,013
Expenses
Interest and debt financing expenses	4,249		7,703
Interest expense on members subordinated notes	2,003		4,448
General and administrative expenses	881		1,351
Total expenses	7,133		13,502
Net investment income (loss)	3,069		6,511
Net realized and unrealized gain (losses)
Net realized gain (loss) on investments	10		21
Net change in unrealized appreciation (depreciation) on investments	(2,225)		(6,267)
Total net gains (losses)	(2,215)		(6,246)
Net increase (decrease) in members' equity resulting from operations	$ 854		$ 265