Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Options (Details)

v3.19.3
Stock-Based Compensation - Options (Details) - Options to purchase common stock - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Jun. 30, 2019
Sep. 30, 2019
Dec. 31, 2018
Options            
Outstanding at the beginning of the period (in shares) 1,654,241 1,768,350 1,887,969 1,887,969 1,887,969  
Granted (in shares)     81,807      
Exercised (in shares) (225,414) (114,109) (200,326)      
Forfeited (in shares) (34,818)   (1,100)      
Outstanding at the end of the period (in shares) 1,394,009 1,654,241 1,768,350 1,654,241 1,394,009 1,887,969
Options exercisable (in shares) 1,332,602       1,332,602  
Weighted-Average Exercise Price            
Outstanding at the beginning of the period (in dollars per share) $ 22.31 $ 21.74 $ 20.05 $ 20.05 $ 20.05  
Granted (in dollars per share)     49.02      
Exercised (in dollars per share) 9.41 13.36 16.91      
Forfeited (in dollars per share) 48.86   31.70      
Outstanding at the end of the period (in dollars per share) 23.74 $ 22.31 $ 21.74 $ 22.31 23.74 $ 20.05
Options exercisable (in dollars per share) $ 22.77       $ 22.77  
Weighted-Average Remaining Contractual Life            
Outstanding     3 years 6 months 3 years 4 months 24 days 3 years 3 months 18 days 3 years 4 months 24 days
Options exercisable         3 years  
Aggregate Intrinsic Value            
Outstanding (in dollars) $ 45,949 $ 76,187 $ 77,197 $ 76,187 $ 45,949 $ 56,046
Options exercisable (in dollars) 45,209       45,209  
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]            
Unrecognized stock-based compensation expense related to unvested stock options $ 987       $ 987  
Unrecognized compensation expense weighted-average recognition period         2 years  
Minimum            
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]            
Exercise prices of stock options outstanding (in dollars per share) $ 7.15       $ 7.15  
Maximum            
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]            
Exercise prices of stock options outstanding (in dollars per share) $ 55.29       $ 55.29