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Stockholders' Equity - Summary of Fair Value of Stock Option Grants (Details)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Risk-free interest rate, minimum 0.60% 0.60%
Risk-free interest rate. maximum 1.00% 0.70%
Expected volatility, minimum 88.70% 82.40%
Expected volatility, maximum 89.50% 84.00%
Expected dividend yield 0.00% 0.00%
Minimum    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected term (in years) 5 years 9 months 18 days 5 years 9 months 18 days
Maximum    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected term (in years) 6 years 25 days 10 years