XML 94 R76.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock Plans and Stock-Based Compensation - Performance-Based Restricted Stock Units - Additional Information (Details) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Stock-based compensation expense $ 25,825,000 $ 9,299,000 $ 3,101,000
Performance-Based Restricted Stock Units      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Share-based compensation, number of stock unit grants in period 288,902    
Stock-based compensation expense $ 1,500,000 $ 0  
Award achievement probability percentage 100.00%    
Unrecognized compensation expense $ 13,900,000    
Weighted-average amortization period 2 years 3 months 18 days    
Number of stock units vested 0    
Performance-Based Restricted Stock Units | Minimum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Share-based compensation, thresholds percentage of revenue growth 20.00%    
Share price $ 23.17    
Performance-Based Restricted Stock Units | Maximum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Share-based compensation, thresholds percentage of revenue growth 40.00%    
Share price $ 58.82    
Performance-Based Restricted Stock Units | Tranche One      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Share-based compensation, compounded annual growth measurement period 2 years    
Share-based compensation, vesting stock percentage 50.00%    
Performance-Based Restricted Stock Units | Tranche Two      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Share-based compensation, compounded annual growth measurement period 3 years