DEBT - Series A Notes Narrative (Details) - Series A Notes - Unsecured Debt - USD ($)	Jun. 30, 2025	Dec. 31, 2024	Jan. 21, 2022	Oct. 21, 2021
Debt Instrument [Line Items]
Debt instrument, face amount	$ 150,000,000	$ 150,000,000	$ 72,500,000	$ 77,500,000
Debt instrument, interest rate, stated percentage (as a percent)				4.04%
Debt instrument, interest rate, below investment grade rating, stated percentage (as a percent)				5.04%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

MSC INCOME FUND, INC. 10-Q