RELATED PARTY TRANSACTIONS - Schedule of Management And Incentive Fee (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Related Party Transaction [Line Items]
Base management fee	$ 5,341	$ 4,907	$ 10,566	$ 9,879
Incentive fee on income	3,117	3,431	6,216	5,454
Incentive fee on capital gains	(2,949)	0	(2,311)	0
Related Party \| Advisory Agreement - Base Management Fees \| MSC Income
Related Party Transaction [Line Items]
Base management fee	5,341	4,907	10,566	9,879
Related Party \| Advisory Agreement - Subordinated Incentive Fees \| MSC Income
Related Party Transaction [Line Items]
Incentive fee on income	3,117	3,431	6,216	5,454
Waiver of incentive fee on income	(258)	0	(1,243)	0
Related Party \| Advisory Agreement - Incentive Fees, Capital Gains Fees \| MSC Income
Related Party Transaction [Line Items]
Incentive fee on capital gains	$ 2,949	$ 0	$ 2,311	$ 0

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Amount of expense for income-based incentive fee for performance under arrangement to manage operation, including, but not limited to, managing investment.

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Amount of expense for investment management fee, including, but not limited to, expense in connection with research, selection, supervision, and custody of investment.

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