Annual report [Section 13 and 15(d), not S-K Item 405]

SUBSEQUENT EVENTS (Details)

v3.25.0.1
SUBSEQUENT EVENTS (Details)
 1 Months Ended 3 Months Ended 213 Months Ended
Jan. 29, 2025
Feb. 28, 2025
$ / shares
Jan. 31, 2025
USD ($)
plan
$ / shares
shares
Jun. 30, 2025
$ / shares
Mar. 31, 2025
$ / shares
Jun. 30, 2024
Jun. 30, 2025
$ / shares
Subsequent Event [Line Items]              
Increase in common stock, dividends, per share, declared, monthly (as a percent)           4.20%  
Forecast | O 2025 Q1 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)         $ 0.75    
Forecast | O 2025 Q1 Including Supplemental Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)         $ 1.05    
Forecast | O 2025 Q2 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)       $ 0.75      
Forecast | O 2025 Q1 Covering Period Since October 2027 Initial Public Offering and Including Supplemental Dividend              
Subsequent Event [Line Items]              
Common stock, dividend, per share, cash paid (in dollars per share)             $ 44.725
Subsequent Event | O 2025 Q1 Supplemental Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   $ 0.30          
Subsequent Event | O 2025 M1 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   0.25          
Subsequent Event | O 2025 M2 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   0.25          
Subsequent Event | O 2025 M3 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   0.25          
Subsequent Event | O 2025 M4 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   0.25          
Subsequent Event | O 2025 M5 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   0.25          
Subsequent Event | O 2025 M6 Dividends              
Subsequent Event [Line Items]              
Common stock, dividend, per share, declared (in dollars per share)   $ 0.25          
Subsequent Event | External Investment Manager | Advisory Agreement, On and AfterJanuary 29, 2025 | Affiliated Entity              
Subsequent Event [Line Items]              
Management and service fees, base rate, percentage of average total assets (as a percent) 1.50%            
Management and service fees, incentive rate (as a percent) 17.50%            
Management and service fees, catch up feature rate (as a percent) 50.00%            
Subsequent Event | MSC Income              
Subsequent Event [Line Items]              
Share repurchase program, authorized, amount | $     $ 65,000,000        
Subsequent Event | MSC Income              
Subsequent Event [Line Items]              
Sale of stock, price per share (in dollars per share)     $ 15.53        
Shares acquired (in shares) | shares     289,761        
Share purchase program, authorized, amount | $     $ 20,000,000        
Share purchase program, period in force     12 months        
Share purchase (repurchase) program, number of active plans | plan     2        
Share purchase program, percentage of outstanding stock maximum (as a percent)     3.00%        
Subsequent Event | Follow-On Offering | MSC Income              
Subsequent Event [Line Items]              
Sale of stock, number of shares issued in transaction (in shares) | shares     6,325,000        
Sale of stock, price per share (in dollars per share)     $ 15.53