Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Options) (Details)

v3.7.0.1
Stock-Based Compensation (Options) (Details) - Stock Options - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Options    
Outstanding at the beginning of the period (in shares) 3,033,194  
Granted (in shares) 75,238  
Exercised (in shares) (208,334)  
Forfeited (in shares) (9,062)  
Outstanding at the end of the period (in shares) 2,891,036 3,033,194
Options exercisable (in shares) 2,612,682  
Weighted-Average Exercise Price    
Outstanding at the beginning of the period (in dollars per share) $ 16.33  
Granted (in dollars per share) 31.70  
Exercised (in dollars per share) 9.12  
Forfeited (in dollars per share) 45.81  
Outstanding at the end of the period (in dollars per share) 17.15 $ 16.33
Options exercisable (in dollars per share) $ 15.50  
Weighted-Average Remaining Contractual Life    
Outstanding 4 years 6 months 4 years 3 months 18 days
Options exercisable 4 years  
Aggregate Intrinsic Value    
Outstanding (in dollars) $ 50,792 $ 63,264
Options exercisable (in dollars) 49,767  
Additional disclosures    
Unrecognized stock-based compensation expense related to unvested stock options $ 4,792  
Unrecognized compensation expense weighted-average recognition period 2 years 3 months 18 days  
Minimum    
Additional disclosures    
Exercise prices of stock options outstanding (in dollars per share) $ 0.11  
Maximum    
Additional disclosures    
Exercise prices of stock options outstanding (in dollars per share) $ 55.29