Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Schedule of Weighted-average Assumptions to Estimate the Fair Value of the Options Granted (Details)

v3.19.3
Stock-Based Compensation - Schedule of Weighted-average Assumptions to Estimate the Fair Value of the Options Granted (Details)
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Share-based Payment Arrangement [Abstract]        
Expected volatility 103.00% 109.00% 108.00% 109.00%
Expected term 6 years 2 months 30 days 5 years 5 years 1 month 2 days 5 years
Risk-free interest rate 1.83% 2.78% 2.21% 2.54%
Expected dividend yield 0.00% 0.00% 0.00% 0.00%