v3.26.3
Consolidated Statements of Changes in Net Assets - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Jun. 30, 2026
Mar. 31, 2026
Sep. 30, 2025
Jun. 30, 2025
Mar. 31, 2025
Sep. 30, 2026
Sep. 30, 2025
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Balance as of beginning of period (in shares)     89,834,849       89,834,849  
Balance as of beginning of period $ 3,166,538 $ 3,093,644 $ 2,993,893 $ 2,884,217 $ 2,840,133 $ 2,797,838 $ 2,993,893 $ 2,797,838
Public offering of common stock, net of offering costs 10,771 18,871 134,283 6,859 10,833 5,198    
Share‑based compensation 5,880 5,807 5,105 5,433 5,416 4,842    
Purchase of vested stock for employee payroll tax withholding   (8,974)   (4) (10,015)      
Dividend reinvestment (in shares)             553,827 471,425
Dividend reinvestment 9,873 10,647 9,961 9,586 9,379 9,087 $ 30,481 $ 28,052
Amortization of directors’ deferred compensation 82 86 90 91 97 108    
Issuance of restricted stock, net of forfeited shares   0     0      
Net increase in net assets resulting from operations 117,083 147,577 48,981 123,671 122,534 116,082 $ 313,641 362,287
Dividends to stockholders $ (102,549) (101,120) (98,669) (95,278) (94,160) (93,022)    
Balance as of ending of period (in shares) 93,742,839           93,742,839  
Balance as of ending of period $ 3,207,678 $ 3,166,538 $ 3,093,644 $ 2,934,575 $ 2,884,217 $ 2,840,133 $ 3,207,678 $ 2,934,575
Common Stock                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Balance as of beginning of period (in shares) 93,359,325 92,462,273 89,838,001 89,282,595 88,659,597 88,400,391 89,838,001 88,400,391
Balance as of beginning of period $ 934 $ 925 $ 898 $ 893 $ 887 $ 884 $ 898 $ 884
Public offering of common stock, net of offering costs (in shares) 198,882 364,392 2,430,825 111,941 195,454 89,091    
Public offering of common stock, net of offering costs $ 2 $ 4 $ 25 $ 1 $ 2 $ 1    
Purchase of vested stock for employee payroll tax withholding (in shares)   (169,445)   (66) (177,024)      
Purchase of vested stock for employee payroll tax withholding   $ (2)     $ (2)      
Dividend reinvestment (in shares) 176,899 203,405 173,523 146,971 167,705 156,749    
Dividend reinvestment $ 1 $ 2 $ 2 $ 1 $ 2 $ 2    
Issuance of restricted stock, net of forfeited shares (in shares) 9,086 498,700 19,924 (4,937) 436,863 13,366    
Issuance of restricted stock, net of forfeited shares   $ 5     $ 4      
Balance as of ending of period (in shares) 93,744,192 93,359,325 92,462,273 89,536,504 89,282,595 88,659,597 93,744,192 89,536,504
Balance as of ending of period $ 937 $ 934 $ 925 $ 895 $ 893 $ 887 $ 937 $ 895
Additional Paid-In Capital                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Balance as of beginning of period 2,633,935 2,607,285 2,457,660 2,429,817 2,413,914 2,394,492 2,457,660 2,394,492
Public offering of common stock, net of offering costs 10,769 18,867 134,258 6,858 10,831 5,197    
Share‑based compensation 5,880 5,807 5,105 5,433 5,416 4,842    
Purchase of vested stock for employee payroll tax withholding   (8,972)   (4) (10,013)      
Dividend reinvestment 9,872 10,645 9,959 9,585 9,377 9,085    
Amortization of directors’ deferred compensation 82 86 90 91 97 108    
Issuance of restricted stock, net of forfeited shares   (5)     (4)      
Dividends to stockholders 231 222 213 207 199 190    
Balance as of ending of period 2,660,769 2,633,935 2,607,285 2,451,987 2,429,817 2,413,914 2,660,769 2,451,987
Total Undistributed Earnings                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Balance as of beginning of period 531,669 485,434 535,335 453,507 425,332 402,462 535,335 402,462
Net increase in net assets resulting from operations 117,083 147,577 48,981 123,671 122,534 116,082    
Dividends to stockholders (102,780) (101,342) (98,882) (95,485) (94,359) (93,212)    
Balance as of ending of period $ 545,972 $ 531,669 $ 485,434 $ 481,693 $ 453,507 $ 425,332 $ 545,972 $ 481,693