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Equity - Schedule of Assumptions Used to Determine Fair Value of and Stock Options Granted (Details) - Stock Options - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expected volatility 70.00% 69.00% 68.00%
Expected volatility 75.00% 71.00% 70.00%
Risk free interest rate 0.30% 1.40% 2.60%
Risk free interest rate 1.60% 2.70% 3.10%
Expected dividend yield 0.00% 0.00% 0.00%
Minimum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expected term (years) 5 years 3 months 18 days 5 years 6 months 5 years
Exercise price $ 22.70 $ 17.29 $ 14.44
Maximum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expected term (years) 7 years 7 years 10 years
Exercise price $ 50.00 $ 37.66 $ 16.24