XML 66 R55.htm IDEA: XBRL DOCUMENT v3.22.0.1
Stock-Based Compensation - Assumptions Using Black-Scholes for Estimated Fair Value of Stock Options (Details) - Options to purchase Common Stock
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Dividend yield 0.00% 0.00%
Expected volatility (weighted-average) 108.00% 105.00%
Expected term (in years) 6 years 5 years 10 months 24 days
Minimum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Risk-free interest rate 0.83% 0.39%
Expected volatility (range) 107.00% 102.00%
Maximum    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Risk-free interest rate 1.30% 0.93%
Expected volatility (range) 110.00% 106.00%