Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Weighted Average Assumptions (Details)

v3.19.3
Stock-based Compensation - Weighted Average Assumptions (Details) - Stock Options [Member]
3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Stock-based awards weighted average assumptions [Abstract]        
Dividend yield 0.00% 0.00% 0.00% 0.00%
Expected volatility 101.00% 101.00% 103.00% 101.00%
Risk-free interest rate 1.71% 2.76% 2.49% 2.72%
Expected term 5 years 5 months 19 days 5 years 7 months 6 days 5 years 7 months 6 days 5 years 7 months 6 days