XML 58 R44.htm IDEA: XBRL DOCUMENT v3.21.2
Stock-Based Compensation - Schedule of Weighted Average Assumptions on Grant Date Fair Value for Options Granted (Details) - Stock Options
9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Expected term (in years) 6 years 1 month 6 days 6 years
Risk-free rate 0.79% 0.36%
Expected volatility 90.00% 140.00%