Quarterly report pursuant to Section 13 or 15(d)

Net Income Per Share - Calculation (Details)

v3.23.2
Net Income Per Share - Calculation (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2023
Mar. 31, 2023
Jun. 30, 2022
Mar. 31, 2022
Jun. 30, 2023
Jun. 30, 2022
Net income - basic and diluted $ 164,400 $ 135,870 $ 143,697 $ 114,711 $ 300,270 $ 258,410
Weighted average number of common shares outstanding - basic 31,599,744   32,405,292   31,575,337 32,570,988
Dilutive effect of common stock equivalents:            
Stock options 84,998   104,486   85,522 114,570
Weighted average number of common shares outstanding - diluted 31,731,807   32,614,449   31,722,660 32,827,549
Basic net income per common share $ 5.20   $ 4.43   $ 9.51 $ 7.93
Diluted net income per common share $ 5.18   $ 4.41   $ 9.47 $ 7.87
Service-based conditions            
Dilutive effect of common stock equivalents:            
Restricted stock awards 25,052   12,123   23,848 13,625
Market-based conditions            
Dilutive effect of common stock equivalents:            
Restricted stock awards 20,039   52,871   22,450 76,515
Performance-based conditions            
Dilutive effect of common stock equivalents:            
Restricted stock awards 1,974   39,677   15,503 51,851