Annual report pursuant to Section 13 and 15(d)

Stock-based Compensation - Stock Option Assumptions (Details)

v3.10.0.1
Stock-based Compensation - Stock Option Assumptions (Details)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Dividend yield 0.00% 0.00%
Risk-free interest rate, minimum 2.68% 1.83%
Risk-free interest rate, maximum 3.00% 2.37%
Volatility, minimum 88.00% 77.00%
Volatility, maximum 106.00% 88.00%
Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term (in years) 5 years 3 months 7 days 5 years 3 months 7 days
Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term (in years) 10 years 9 years 2 months 23 days