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RELATED PARTY TRANSACTIONS - Base Management Subordinated Incentive Fees (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Related Party Transaction [Line Items] |  |
Base management fees | $ 4,972 | $ 5,028
Investment Company, Contractual Fee Waived | 0 | (2,111)
Related Party | Advisory Agreement - Base Management Fees | MSC Income |  |
Related Party Transaction [Line Items] |  |
Base management fees | 4,972 | 5,028
Related Party | Advisory Agreement - Subordinated Incentive Fees | MSC Income |  |
Related Party Transaction [Line Items] |  |
Base management fees | 2,023 | 3,637
Related Party | Advisory Agreement - Incentive Fees, Capital Gains Fees | MSC Income |  |
Related Party Transaction [Line Items] |  |
Base management fees | 0 | 0
Related Party | Advisory Agreement - Internal Administrative Services | MSC Income |  |
Related Party Transaction [Line Items] |  |
Base management fees | 174 | 2,267
Investment Company, Contractual Fee Waived | $ 0 | $ (2,111)

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