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Stock-Based Compensation - Option Pricing Assumptions (Details) - $ / shares
3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected dividend yield 0.00% 0.00%
Expected term (in years) 5 years 11 months 12 days 6 years 3 months
Weighted- Average Exercise Price, Expired (in dollars per share) $ 21.16  
Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected volatility 87.90% 86.40%
Risk-free interest rate 1.50% 0.60%
Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected volatility 88.30% 86.70%
Risk-free interest rate 2.40% 1.40%