Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Payments - Stock Options (Details)

v3.7.0.1
Stock-Based Payments - Stock Options (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Stock-based payments    
Unrecognized compensation costs $ 13,000  
Aggregate Intrinsic Value    
Intrinsic value of options exercised $ 500  
Stock options    
Stock-based payments    
Vesting period 4 years  
Shares    
Outstanding at beginning of year (in shares) 2,543,435  
Granted (in shares) 864,000  
Exercised (in shares) (50,508)  
Cancelled (in shares) (198,369)  
Outstanding at end of period (in shares) 3,158,558 2,543,435
Exercisable (in shares) 908,893  
Vested and expected to vest (in shares) 3,158,558  
Weighted Average Exercise Price    
Outstanding at beginning of year (in dollars per share) $ 6.44  
Granted (in dollars per share) 10.91  
Exercised (in dollars per share) 2.78  
Cancelled (in dollars per share) 5.17  
Outstanding at end of period (in dollars per share) 7.81 $ 6.44
Exercisable (in dollars per share) 3.74  
Vested and expected to vest (in dollars per share) $ 7.81  
Remaining Contractual Life    
Outstanding 8 years 2 months 12 days 8 years 3 months 18 days
Exercisable 6 years  
Vested and expected to vest 8 years 2 months 12 days  
Aggregate Intrinsic Value    
Outstanding $ 25,554 $ 14,898
Exercisable 11,082  
Vested and expected to vest 25,554  
Performance-based stock options    
Stock-based payments    
Unrecognized compensation costs $ 900  
Performance-based stock options | Maximum    
Stock-based payments    
Vesting period 6 years  
Performance-based stock options | Advisor    
Shares    
Granted (in shares)   75,000