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Stockholder's Equity - Additional Information (Detail) - shares
3 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Common stock, shares issued 35,162,043 34,843,885
2014 Plan [Member]    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Common stock reserved for future issuance 1,158,000  
Percentage of common stock issued and outstanding increase annually 4.50%  
Number of common stock shares subject to outstanding awards 6,090,000  
Employee Stock Purchase Plan [Member]    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Percentage of common stock issued and outstanding increase annually 1.00%  
Number of shares reserved 150,000  
Additional shares issued 300,000  
Common stock, shares issued 136,000