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Stock Based Compensation - Summary of Estimated Fair Value of Stock Option Grant Determined on Grant Date Using black-Scholes Valuation Model (Details) - Employee Stock Option - $ / shares
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Weighted-average grant date fair value $ 8.63 $ 1.36
Dividend yield 0.00% 0.00%
Volatility 111.00% 94.00%
Risk-free interest rate 1.00% 0.71%
Expected life of options (years) 6 years 5 years 10 months 24 days