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Share-based Compensation - Fair Value of Each Option Grant Estimated (Details)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate minimum   2.24%
Risk-free interest rate maximum   2.85%
Expected volatility minimum   47.51%
Expected volatility maximum   47.89%
Dividend yield 0.00% 0.00%
Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected option life (in years)   10 months 17 days
Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected option life (in years)   5 years 10 months 2 days