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Stock Plans and Stock-Based Compensation - 2016 Employee Stock Purchase Plan - Additional Information (Details) - USD ($)
$ in Thousands
12 Months Ended
Sep. 15, 2016
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Shares reserved for issuance   4,400,000    
Total recognized compensation cost   $ 33,489 $ 25,825 $ 9,299
2016 Employee Stock Purchase Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Shares reserved for issuance 500,000      
Purchase price as percentage of fair market value of common stock 85.00%      
Shares purchased under the plan   42,481 74,517 128,786
Total recognized compensation cost   $ 900 $ 700 $ 600
Cost amortized weighted-average period   3 months    
Unrecognized compensation cost   $ 200    
Maximum | 2016 Employee Stock Purchase Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Increase in number of shares reserved and available for issuance 200,000      
Common Stock | 2016 Employee Stock Purchase Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Increase in number of shares reserved and available for issuance, percentage 1.00%      
Common Stock | Maximum | 2016 Employee Stock Purchase Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Purchase price, discount percentage 15.00%