Quarterly report pursuant to Section 13 or 15(d)

Income (Loss) Per Share - Calculation (Details)

v3.10.0.1
Income (Loss) Per Share - Calculation (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Net income - basic and diluted $ 42,658 $ 31,393 $ 96,198 $ 53,142
Weighted average number of common shares outstanding - basic 35,091,388 35,022,113 35,084,694 36,203,497
Dilutive effect of common stock equivalents:        
Stock options 286,495 296,500 316,104 249,019
Weighted average number of common shares outstanding - diluted 35,789,383 35,737,629 35,815,357 36,842,144
Basic net income per common share $ 1.22 $ 0.90 $ 2.74 $ 1.47
Diluted net income per common share $ 1.19 $ 0.88 $ 2.69 $ 1.44
Service-based conditions        
Dilutive effect of common stock equivalents:        
Restricted stock awards 135,347 216,724 161,474 215,069
Market-based conditions        
Dilutive effect of common stock equivalents:        
Restricted stock awards 252,278 202,292 245,127 174,559
Performance-based conditions        
Dilutive effect of common stock equivalents:        
Restricted stock awards 23,875   7,958