Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Assumptions (Details)

v3.20.4
Stockholders' Equity - Assumptions (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Minimum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate (as a percent) 0.20% 1.40% 2.70%
Expected volatility (as a percent) 47.00% 40.00% 33.00%
Expected term 4 years 8 months 12 days 4 years 7 months 6 days 5 years 1 month 6 days
Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate (as a percent) 1.40% 2.60% 3.00%
Expected volatility (as a percent) 71.00% 49.00% 36.00%
Expected term 5 years 1 month 6 days 5 years 10 months 24 days 5 years 9 months 18 days