v3.26.1
Financial Highlights (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Mar. 31, 2026
Dec. 31, 2025
Mar. 31, 2025
Dec. 31, 2024
Per share data                
Net asset value at beginning of period (in dollars per share)     $ 12.13 $ 11.66        
Net investment income (in dollars per share)     0.98 0.96        
Net realized gain (loss) (in dollars per share)     0.04 (0.34)        
Net unrealized appreciation (depreciation) (in dollars per share)     (0.08) 0.13        
Total from investment operations (in dollars per share)     0.94 0.75        
Net increase (decrease) in net assets from capital share transactions (in dollars per share)     (0.01) 0.33        
Distributions of net investment income (in dollars per share)     (0.95) (0.95)        
Stock-based compensation expense included in net investment income and other movements (in dollars per share)     0.04 0.05        
Net asset value at ending of period (in dollars per share) $ 12.15 $ 11.84 12.15 11.84        
Ratios and supplemental data:                
Per share market value at end of period (in dollars per share) $ 15.77 $ 18.28 $ 15.77 $ 18.28        
Total return     (11.04%) (4.38%)        
Shares outstanding at end of period (in shares) 187,218 181,729 187,218 181,729        
Weighted average shares outstanding (in shares) 185,517 176,809 184,146 173,231        
Net assets at end of period $ 2,274,330 $ 2,151,075 $ 2,274,330 $ 2,151,075 $ 2,226,995 $ 2,216,053 $ 2,000,630 $ 1,989,581
Ratio of total expense to average net assets     9.88% 8.87%        
Ratio of net investment income before investment gains and losses to average net assets     16.31% 16.24%        
Portfolio turnover rate     18.54% 12.48%        
Weighted average debt outstanding $ 2,409,041 $ 2,045,905 $ 2,414,679 $ 1,931,719        
Weighted average debt per common share (in dollars per share)     $ 13.11 $ 11.15