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Stock-based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Shares of common stock reserved for issuance (in shares) 2,400,000  
Shares of common stock available for issuance (in shares) 616,820  
Restricted Stock Units (RSUs)    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share settlement under RSUs (in shares) 22,977 13,024
Cash used for employee withholding tax payments $ 2,500,000 $ 1,000,000
Unamortized stock-based compensation expense $ 23,600,000  
Weighted-average remaining amortization period 2 years 1 month 6 days  
Stock Options    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Term 3 years  
Stock-based compensation expense $ 3,500,000 $ 3,300,000
Contractual life 10 years  
Restricted Stock Units (RSUs), Performance-Based    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Awards granted (in shares) 24,784  
Stock-based compensation expense $ 100,000  
Performance Share Units (PSUs)    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Awards granted (in shares) 48,241  
Stock-based compensation expense $ 0  
Minimum | Restricted Stock Units (RSUs)    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Term 1 year  
Maximum | Restricted Stock Units (RSUs)    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Term 3 years