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v3.25.3

RELATED PARTY TRANSACTIONS - Narrative (Details) |  |  |  | 9 Months Ended
--- | --- | --- | --- | ---
Jan. 29, 2025 | Dec. 11, 2024 | Oct. 30, 2020 component | Sep. 30, 2025 shares
Related Party | Main Street |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Shares acquired (in shares) | shares |  |  |  | 1,433,573
MSC Income | Advisory Agreement |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Advisory agreement |  | 2 years |  |
MSC Income | Advisory Agreement | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Number of components related to incentive fee | component |  |  | 2 |
Base fee rate (as a percent) | 1.25% |  |  | 1.50%
Advisory agreement, average total assets threshold (as a percent) | 7.50% |  |  |
MSC Income | Advisory Agreement, Incentive Rate, Pre-Incentive Fee Net Investment Income | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 17.50% |  | 20.00% |
MSC Income | Advisory Agreement - Incentive Rate, Quarterly Hurdle Rate | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 1.50% |  | 1.875% |
Base fee rate (as a percent) | 20.00% |  |  |
Advisory agreement, average total assets threshold (as a percent) | 1.00% |  |  |
MSC Income | Advisory Agreement - Incentive Rate, Annualized Hurdle Rate | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 6.00% |  | 7.50% |
MSC Income | Advisory Agreement, Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 50.00% |  | 100.00% |
MSC Income | Advisory Agreement - Incentive Rate, Quarterly Catch-Up Threshold | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 2.30769% |  | 2.34375% |
MSC Income | Advisory Agreement - Incentive Rate, Annualized Catch-Up Threshold | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 9.23077% |  | 9.375% |
MSC Income | Advisory Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold | Related Party |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Incentive fee rate (as a percent) | 17.50% |  | 20.00% |

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