Quarterly report pursuant to Section 13 or 15(d)

Equity - Summary of Assumptions Used (Details)

v3.19.2
Equity - Summary of Assumptions Used (Details) - Employee Stock Option
6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Class of Stock    
Risk free interest rate, minimum (percent) 0.95% 0.95%
Risk free interest rate, maximum (percent) 2.24% 2.24%
Volatility, minimum (percent) 70.18% 70.18%
Volatility, maximum (percent) 89.11% 89.11%
Expected dividend yield (percent) 0.00% 0.00%
Minimum    
Class of Stock    
Expected life (years) 5 years 5 years
Maximum    
Class of Stock    
Expected life (years) 6 years 3 months 6 years 3 months