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Share-based Compensation - Summary of Fair Value of Each Option Grant Estimated Throughout Year Using Black-Scholes Option-pricing Model (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Abstract]    
Expected term (in years) 6 years 2 months 12 days 6 years 2 months 12 days
Expected stock price volatility 89.50% 89.70%
Risk-free interest rate 1.17% 2.26%
Expected dividend yield 0.00% 0.00%