Annual report pursuant to Section 13 and 15(d)

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

v3.6.0.2
Stock Options - Summary of Outstanding Stock Option Activity (Details) - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]        
Number of shares, Beginning balance 756,692 504,550 364,450  
Number of shares, Granted 359,319 512,402 255,600  
Number of shares, Exercised (58,155) (24,260) (100)  
Number of shares, Expired/Forfeited (17,469) (236,000) (115,400)  
Number of shares, Ending balance 1,040,387 756,692 504,550 364,450
Number of shares, Vested and exercisable 628,933      
Number of shares, Vested and expected to vest 1,012,596      
Weighted average exercise price, Beginning balance $ 2.10 $ 2.60 $ 2.73  
Weighted average exercise price, Granted 2.60 2.00 2.70  
Weighted average exercise price, Exercised 2.36 3.19 2.20  
Weighted average exercise price, Expired/Forfeited 2.13 2.77 3.22  
Weighted average exercise price, Ending balance 2.25 $ 2.10 $ 2.60 $ 2.73
Weighted average exercise price, Vested and exercisable 2.05      
Weighted average exercise price, Vested and expected to vest $ 2.24      
Weighted average remaining contractual term 7 years 9 months 18 days 7 years 7 months 6 days 5 years 9 months 18 days 4 years 3 months 18 days
Weighted average remaining contractual term, Granted 9 years 4 months 24 days 9 years 2 months 12 days 9 years 2 months 12 days  
Weighted average remaining contractual term, Exercised 3 years 6 months      
Weighted average remaining contractual term, Expired/Forfeited 2 years 7 months 6 days      
Weighted average remaining contractual term, Vested and exercisable 7 years      
Weighted average remaining contractual term, Vested and expected to vest 7 years 9 months 18 days