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Stock-Based Compensation - Summary of Assumptions Used to Estimate the Fair Value of Stock Options and Employee Stock Purchase Plan (Details)
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Employee Stock Purchase Plan    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected life (in years) 6 months 6 months
Risk-free interest rate 1.59% 2.50%
Volatility 55.00% 35.00%
Stock Options    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected life (in years) 6 years 7 days 6 years 7 days
Risk-free interest rate 0.96% 2.66%
Volatility 50.00% 50.00%