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Stock Plans and Stock-Based Compensation - Performance-Based Restricted Stock Units - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Stock-based compensation expense $ 33,489 $ 25,825 $ 9,299
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 389,018    
Stock-based compensation expense $ 10,600 $ 1,500  
Award achievement probability percentage 100.00%    
Weighted-average grant date fair values of units granted $ 80.87 $ 55.99  
Number of stock units vested 0 0  
Unrecognized compensation expense $ 30,300    
Weighted-average amortization period 2 years    
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 $ 54.83    
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 $ 98.92    
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