Quarterly report pursuant to Section 13 or 15(d)

FINANCIAL HIGHLIGHTS (Details)

v3.23.3
FINANCIAL HIGHLIGHTS (Details) - USD ($)
$ / shares in Units, $ in Thousands
 9 Months Ended
Sep. 30, 2023
Sep. 30, 2022
Jun. 30, 2023
Mar. 31, 2023
Dec. 31, 2022
Jun. 30, 2022
Mar. 31, 2022
Dec. 31, 2021
Investment Company, Financial Highlights [Roll Forward]                
NAV at the beginning of the period (in dollars per share) $ 26.86 $ 25.29            
Net investment income (in dollars per share) 3.07 2.31            
Net realized gain (loss) (in dollars per share) (1.27) 0.05            
Net unrealized appreciation (depreciation) (in dollars per share) 2.06 (0.28)            
Income tax benefit (provision) (in dollars per share) (0.29) (0.24)            
Net increase in net assets resulting from operations (in dollars per share) 3.57 1.84            
Dividends paid from net investment income (in dollars per share) (2.72) (2.19)            
Dividends paid (in dollars per share) (2.72) (2.19)            
Impact of the net change in monthly dividends declared prior to the end of the period and paid in the subsequent period (in dollars per share) (0.01) 0            
Accretive effect of stock offerings (issuing shares above NAV per share) (in dollars per share) 0.58 0.98            
Accretive effect of DRIP issuance (issuing shares above NAV per share) (in dollars per share) 0.08 0.08            
Other (in dollars per share) (0.03) (0.06)            
NAV at the end of the period (in dollars per share) 28.33 25.94            
Market value at the end of the period (in dollars per share) $ 40.63 $ 33.64            
Shares outstanding at the end of the period (in shares) 83,677,488 76,308,830            
NAV at end of period $ 2,370,807 $ 1,979,420 $ 2,254,948 $ 2,172,922 $ 2,108,586 $ 1,865,163 $ 1,873,654 $ 1,788,846
Average NAV 2,226,816 1,876,771            
Average outstanding debt $ 1,989,900 $ 1,880,100            
Investment Company, Ratio To Average Net Assets [Abstract]                
Ratio of total expenses, including income tax expense, to average NAV 6.54% 5.92%            
Ratio of operating expenses to average NAV 5.49% 4.99%            
Ratio of operating expenses, excluding interest expense, to average NAV 1.98% 2.05%            
Ratio of net investment income to average NAV 11.18% 9.03%            
Portfolio turnover ratio 11.17% 12.46%            
Total investment return 17.72% (20.81%)            
Total return based on change in NAV 13.72% 7.56%            
Related Party | External Investment Manager                
Investment Company, Ratio To Average Net Assets [Abstract]                
Total expenses $ 16,100 $ 9,600