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Stock Plans and Stock-Based Compensation - Schedule of Stock Option Activity (Details) - $ / shares
3 Months Ended 12 Months Ended
Mar. 31, 2018
Dec. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Stock options outstanding, Beginning Balance 2,440,290  
Stock options outstanding, Granted 459,353 1,096,881
Stock options outstanding, Exercised (153,744) (497,175)
Stock options outstanding, Forfeited (28,366) (43,841)
Stock options outstanding, Ending Balance 2,717,533 1,884,425
Weighted average exercise price, Beginning Balance $ 16.55 $ 10.02
Weighted average exercise price, Granted 33.06 22.84
Weighted average exercise price, Exercised 9.53 5.77
Weighted average exercise price, Forfeited 11.30 15.60
Weighted average exercise price, Ending Balance $ 19.79 $ 16.55