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Common Stock and Stock-Based Compensation - Fair Value of Share Options Granted (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest minimum rate 1.42% 2.30% 1.70%
Risk-free interest maximum rate 2.61% 3.07% 2.42%
Volatility maximum rate 50.73% 43.76% 28.56%
Volatility minimum rate 40.83% 43.76% 37.63%
Expected dividend yield 0.00% 0.00% 0.00%
Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected term (in years) 1 year 6 months 4 days 5 years 6 months 5 years 6 months
Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected term (in years) 9 years 4 months 28 days 6 years 29 days 7 years