XML 91 R77.htm IDEA: XBRL DOCUMENT v3.21.1
Stock-Based Compensation - Schedule of Fair Value of Stock Options Assumption (Details) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share-based Payment Arrangement [Abstract]    
Volatility - range 104.00% 107.60%
Risk-free rate 0.28% 2.23%
Contractual term 5 years 6 months 5 years 6 months
Exercise price $ 2.09 $ 3.01