Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions (Details)

v3.19.2
Stockholders' Equity - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions (Details)
6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Dividend yield 0.00% 0.00%
Risk-free interest rate, minimum 1.90% 2.68%
Risk-free interest rate, maximum 2.54% 2.97%
Expected volatility, minimum 105.20% 116.30%
Expected volatility, maximum 106.10% 137.33%
Expected life (in years) 5 years  
Minimum [Member]    
Expected life (in years)   5 years
Maximum [Member]    
Expected life (in years)   10 years