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Stockholders' Equity (Details 2)
12 Months Ended
Dec. 31, 2018
$ / shares
Dividend yield 0.00%
Minimum [Member]  
Fair value of common stock $ 1.62
Expected volatility 111.81%
Risk-free interest 2.79%
Expected life (years) 5 years 1 month 17 days
Maximum [Member]  
Fair value of common stock $ 13.26
Expected volatility 151.79%
Risk-free interest 3.00%
Expected life (years) 5 years 6 months