Quarterly report pursuant to Section 13 or 15(d)

Equity Inventive Plans, Employee Stock Purchase Plan and Stock-Based Compensation - Schedule of Employee Stock Options Valuation (Details)

v3.19.1
Equity Inventive Plans, Employee Stock Purchase Plan and Stock-Based Compensation - Schedule of Employee Stock Options Valuation (Details)
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Line Items]    
Expected term (in years) 4 years  
Expected volatility   58.00%
Expected volatility, Minimum 72.89%  
Expected volatility, Maximum 74.89%  
Risk-free interest rate, Minimum 2.40% 2.72%
Risk-free interest rate, Maximum 2.55% 2.73%
Minimum    
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Line Items]    
Expected term (in years)   5 years 11 months 19 days
Maximum    
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Line Items]    
Expected term (in years)   6 years 29 days