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Stockholders' Equity (Details 3) - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Fair value of common stock $ 2.32  
Expected volatility 151.76%  
Dividend yield 0.00% 0.00%
Risk-free interest 2.70%  
Expected life (years) 5 years 6 months  
Minimum    
Fair value of common stock   $ 1.62
Expected volatility   118.10%
Risk-free interest   2.79%
Expected life (years)   5 years 1 month 17 days
Maximum    
Fair value of common stock   $ 13.26
Expected volatility   151.79%
Risk-free interest   3.00%
Expected life (years)   5 years 6 months