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Stock-Based Compensation - Schedule of Assumptions to Estimate Fair Value of Stock Options Using Black-Scholes Option Pricing Model (Details) - $ / shares
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Expected volatility, minimum 78.00% 77.10% 77.90% 72.60%
Expected volatility, maximum 78.20% 96.40% 79.80% 96.30%
Risk free rates, minimum 0.90% 0.10% 0.10% 0.10%
Risk free rates, maximum 1.20% 0.40% 1.20% 1.70%
Dividend rate 0.00% 0.00% 0.00% 0.00%
Minimum        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Fair value of common stock $ 7.84 $ 5.96 $ 7.84 $ 4.85
Expected term 5 years 7 months 6 days 1 year 10 months 24 days 1 year
Maximum        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Fair value of common stock $ 8.35 $ 10.66 $ 16.82 $ 10.66
Expected term 6 years 1 month 6 days 6 years 1 month 6 days 6 years 1 month 6 days 6 years 1 month 6 days