Quarterly report pursuant to Section 13 or 15(d)

Changes in Equity - Schedule of Stockholders' Equity (Details)

v3.21.2
Changes in Equity - Schedule of Stockholders' Equity (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2021
Jun. 30, 2021
Mar. 31, 2021
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Sep. 30, 2021
Sep. 30, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance $ 547,177 $ 513,935 $ 485,184 $ 472,939 $ 445,343 $ 512,137 $ 485,184 $ 512,137
Net income 83,837 57,046 50,052 46,275 27,583 57,401 190,935 131,258
Dividends paid (21,312) (21,329) (21,329)     (124,098)    
Repurchases of common stock (8,689) (2,504)            
Conversion of Sub-shares into shares of common stock     0          
Other comprehensive income 29 29 28 13 13 14 86 40
Ending balance $ 601,042 $ 547,177 $ 513,935 $ 519,227 472,939 445,343 $ 601,042 $ 519,227
Cash dividends per Sub-share Certificate (in dollars per share) $ 2.75 $ 2.75 $ 2.75 $ 0     $ 8.25 $ 16.00
Cumulative effect of accounting change                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance         $ 0 (111)   $ (111)
Ending balance           $ 0    
Sub-share Certificates                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance (in shares) 0 0 7,756,156 7,756,156 7,756,156 7,756,156 7,756,156 7,756,156
Conversion of Sub-shares into shares of common stock (in shares)     (7,756,156)          
Ending balance (in shares) 0 0 0 7,756,156 7,756,156 7,756,156 0 7,756,156
Common Stock                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance (in shares) 7,754,523 7,756,156 0       0  
Beginning balance $ 78 $ 78 $ 0       $ 0  
Repurchases of common stock (in shares) (6,179) (1,633)            
Conversion of Sub-shares into shares of common stock (in shares)     7,756,156          
Conversion of Sub-shares into shares of common stock     $ 78          
Ending balance (in shares) 7,748,344 7,754,523 7,756,156       7,748,344  
Ending balance $ 78 $ 78 $ 78       $ 78  
Treasury Stock                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance (in shares) 1,633 0 0       0  
Beginning balance $ (2,504) $ 0 $ 0       $ 0  
Repurchases of common stock (in shares) 6,179 1,633         7,812  
Repurchases of common stock $ (8,689) $ (2,504)            
Ending balance (in shares) 7,812 1,633 0       7,812  
Ending balance $ (11,193) $ (2,504) $ 0       $ (11,193)  
Accum. Other Comp. Loss                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance (2,636) (2,665) (2,693) $ (1,434) $ (1,447) $ (1,461) (2,693) $ (1,461)
Other comprehensive income 29 29 28 13 13 14    
Ending balance (2,607) (2,636) (2,665) (1,421) (1,434) (1,447) (2,607) (1,421)
Retained Earnings                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance 552,239 516,522 0       0  
Net income 83,837 57,046 50,052          
Dividends paid (21,312) (21,329) (21,329)          
Conversion of Sub-shares into shares of common stock     487,799          
Ending balance 614,764 552,239 516,522       614,764  
Net Proceeds from All Sources                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance 0 0 487,877 474,373 446,790 513,598 487,877 513,598
Net income       46,275 27,583 57,401    
Dividends paid           (124,098)    
Conversion of Sub-shares into shares of common stock     (487,877)          
Ending balance $ 0 $ 0 $ 0 $ 520,648 474,373 446,790 $ 0 520,648
Net Proceeds from All Sources | Cumulative effect of accounting change                
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Beginning balance         $ 0 (111)   $ (111)
Ending balance           $ 0