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Schedule of Fair Values of Stock Options Granted Using Black-scholes Valuation Model Assumptions (Details)
6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Retirement Benefits [Abstract]    
Expected term of stock options (in years) 5 years 7 months 6 days 5 years 9 months 18 days
Expected stock price volatility 75.00% 73.00%
Risk free interest rate 1.00% 0.50%
Expected dividend yield 0.00% 0.00%