Quarterly report pursuant to Section 13 or 15(d)

RELATED PARTY TRANSACTIONS (Details)

v3.24.3
RELATED PARTY TRANSACTIONS (Details)
 3 Months Ended 9 Months Ended
Aug. 01, 2024
USD ($)
$ / shares
shares
Oct. 30, 2020
component
Sep. 30, 2024
USD ($)
Sep. 30, 2023
USD ($)
Jun. 30, 2023
USD ($)
Sep. 30, 2024
USD ($)
Sep. 30, 2023
USD ($)
Dec. 31, 2023
USD ($)
Related Party Transaction [Line Items]                
Services expenses     $ 5,338,000 $ 4,994,000   $ 15,545,000 $ 14,761,000  
Waiver of internal administrative services expenses     2,206,000 2,014,000   6,678,000 6,297,000  
Accounts payable and other liabilities     3,609,000     3,609,000   $ 255,000
MSC Income | Advisory Agreement | Related Party                
Related Party Transaction [Line Items]                
Base fee rate (as a percent)   1.75%            
Number of components related to incentive fee | component   2            
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)   20.00%            
MSC Income | Advisory Agreement - Incentive Rate, Quarterly Hurdle Rate | Related Party                
Related Party Transaction [Line Items]                
Incentive fee rate (as a percent)   1.875%            
MSC Income | Advisory Agreement - Incentive Rate, Annualized Hurdle Rate | Related Party                
Related Party Transaction [Line Items]                
Incentive fee rate (as a percent)   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)   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)   2.34375%            
MSC Income | Advisory Agreement - Incentive Rate, Annualized Catch-Up Threshold | Related Party                
Related Party Transaction [Line Items]                
Incentive fee rate (as a percent)   9.375%            
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)   20.00%            
MSC Income | Advisory Agreement - Base Management Fees | Related Party                
Related Party Transaction [Line Items]                
Services expenses     5,300,000 5,000,000.0   15,500,000 14,800,000  
MSC Income | Advisory Agreement - Subordinated Incentive Fees | Related Party                
Related Party Transaction [Line Items]                
Services expenses     2,100,000 2,600,000   9,400,000 8,900,000  
MSC Income | Advisory Agreement - Incentive Fees, Capital Gains Fees | Related Party                
Related Party Transaction [Line Items]                
Services expenses     0 0   0 0  
MSC Income | Advisory Agreement - Internal Administrative Services | Related Party                
Related Party Transaction [Line Items]                
Services expenses     2,400,000 2,200,000   7,200,000 6,800,000  
Waiver of internal administrative services expenses     2,200,000 $ 2,000,000.0   $ 6,700,000 $ 6,300,000  
MSC Income - HMS Adviser | Offering Costs | Related Party                
Related Party Transaction [Line Items]                
Percentage of payment of offering costs (as a percent)           1.50%    
Accounts payable and other liabilities     $ 600,000     $ 600,000    
Fee paid indirectly         $ 100,000      
Main Street | Related Party | Dividend Reinvestment Plan                
Related Party Transaction [Line Items]                
Sale of stock, number of shares (in shares) | shares 250,627              
Sale of stock, price per share (in dollars per share) | $ / shares $ 7.98              
Sale of stock, proceeds $ 2,000,000.0