XML 66 R55.htm IDEA: XBRL DOCUMENT v3.8.0.1
Stock Options - Summary of Outstanding Stock Option Activity (Details) - $ / shares
 3 Months Ended 12 Months Ended
Mar. 31, 2018
Dec. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Number of shares, Beginning balance 1,203,627  
Number of shares, Granted 638,300  
Number of shares, Exercised (52,970)  
Number of shares, Expired/Forfeited (53,499)  
Number of shares, Ending balance 1,735,458 1,203,627
Number of shares, Vested and exercisable 499,046  
Number of shares, Vested and expected to vest 1,735,458  
Weighted average exercise price, Beginning balance $ 7.06  
Weighted average exercise price, Granted 10.75  
Weighted average exercise price, Exercised 1.96  
Weighted average exercise price, Expired/Forfeited 9.55  
Weighted average exercise price, Ending balance 8.49 $ 7.06
Weighted average exercise price, Vested and exercisable 2.25  
Weighted average exercise price, Vested and expected to vest $ 8.49  
Weighted average remaining contractual term 8 years 6 months 25 days 8 years 1 month 6 days
Weighted average remaining contractual term, Granted 9 years 9 months 21 days  
Weighted average remaining contractual term, Exercised 3 years 11 months 1 day  
Weighted average remaining contractual term, Expired/Forfeited 21 days  
Weighted average remaining contractual term, Vested and exercisable 6 years 8 months 19 days  
Weighted average remaining contractual term, Vested and expected to vest 8 years 6 months 25 days