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Stock Options and Warrants (Details) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Minimum [Member]    
Expected life (in years) 2 years 6 months 4 years 10 months 25 days
Maximum [Member]    
Expected life (in years) 4 years 6 years 9 months 18 days
Employee Stock Option [Member]    
Dividend yield 0.00% 0.00%
Weighted-average grant date fair value per share $ 0.64 $ 0.50
Employee Stock Option [Member] | Minimum [Member]    
Risk-free interest rates 0.22% 1.87%
Expected life (in years) 2 years 6 months 4 years 10 months 25 days
Expected volatility 71.50% 65.80%
Employee Stock Option [Member] | Maximum [Member]    
Risk-free interest rates 1.61% 2.60%
Expected life (in years) 4 years 6 years 9 months 18 days
Expected volatility 75.40% 72.40%