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Stock Incentive Plans - Schedule of Assumptions Used in Black-Scholes Option Pricing Model to Estimate Fair Value of Stock Options (Details) - Stock Options - Employees and Directors
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Risk-free interest rate, minimum 0.40% 0.40% 1.40%
Risk-free interest rate, maximum 1.40% 0.50% 2.60%
Expected volatility, minimum 92.00% 94.00% 80.00%
Expected volatility, maximum 95.00% 95.00% 83.00%
Minimum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expected term (in years) 5 years 5 years 6 months 5 years 6 months
Maximum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expected term (in years) 7 years 6 years 1 month 6 days 6 years 9 months 18 days