Quarterly report pursuant to Section 13 or 15(d)

Stock Options - Summary of Outstanding Stock Option Activity (Details)

v3.10.0.1
Stock Options - Summary of Outstanding Stock Option Activity (Details) - $ / shares
9 Months Ended 12 Months Ended
Sep. 30, 2018
Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Number of shares, Beginning balance 1,203,627  
Number of shares, Granted 998,800  
Number of shares, Exercised (297,719)  
Number of shares, Expired/Forfeited (425,054)  
Number of shares, Ending balance 1,479,654 1,203,627
Number of shares, Vested and exercisable 488,427  
Number of shares, Vested and expected to vest 1,479,654  
Weighted average exercise price, Beginning balance $ 7.06  
Weighted average exercise price, Granted 9.90  
Weighted average exercise price, Exercised 2.07  
Weighted average exercise price, Expired/Forfeited 11.87  
Weighted average exercise price, Ending balance 8.60 $ 7.06
Weighted average exercise price, Vested and exercisable 5.83  
Weighted average exercise price, Vested and expected to vest $ 8.60  
Weighted average remaining contractual term 8 years 3 months 3 days 8 years 1 month 6 days
Weighted average remaining contractual term, Granted 7 years 3 months 29 days  
Weighted average remaining contractual term, Exercised 10 months 28 days  
Weighted average remaining contractual term, Expired/Forfeited 14 days  
Weighted average remaining contractual term, Vested and exercisable 6 years 10 months 28 days  
Weighted average remaining contractual term, Vested and expected to vest 8 years 3 months 3 days