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Summary of Significant Accounting Policies - Summary of Stock-Based Compensation Assumptions (Details) - Stock Options
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Employees and Directors      
Summary of assumptions used to estimate the fair value of stock options      
Risk-free interest rate 0.91% 0.63% 2.42%
Expected volatility 93.00% 78.00% 70.00%
Expected life in years 6 years 6 years 6 years
Dividend yield 0.00% 0.00% 0.00%
Non Employee      
Summary of assumptions used to estimate the fair value of stock options      
Risk-free interest rate 1.45% 0.82% 2.45%
Expected volatility 87.00% 76.00% 88.00%
Expected life in years 10 years 10 years 10 years
Dividend yield 0.00% 0.00% 0.00%