Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Summary of Stock Option Activity (Detail)

v3.10.0.1
Stockholders' Equity - Summary of Stock Option Activity (Detail) - USD ($)
$ / shares in Units, $ in Thousands
9 Months Ended
Sep. 30, 2018
Sep. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Exercised, Shares (781,191) 0
2014 EIP and 2018 IP    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Outstanding, Shares, beginning balance 5,229,648  
Granted, Shares 2,633,950  
Exercised, Shares (781,191)  
Forfeited or expired, Shares (750,208)  
Outstanding, Shares, ending balance 6,332,199  
Vested and expected to vest, Shares 6,332,199  
Exercisable, Shares 2,258,774  
Outstanding, Weighted Average Exercise Price, beginning balance $ 21.06  
Granted, Weighted Average Exercise Price 38.55  
Exercised, Weighted Average Exercise Price 22.53  
Forfeited or expired, Weighted Average Exercise price 30.00  
Outstanding, Weighted Average Exercise Price, ending balance 27.10  
Stock options vested and expected to vest, Weighted Average Exercise Price 27.10  
Exercisable, Weighted Average Exercise Price $ 21.26  
Outstanding, Weighted Average Remaining Contractual Term 5 years 4 months 24 days  
Stock options vested and expected to vest, Weighted Average Remaining Contractual Term 5 years 4 months 24 days  
Exercisable, Weighted Average Remaining Contractual Term 4 years  
Aggregate intrinsic value $ 92,326  
Vested and expected to vest, Aggregate Intrinsic Value 92,326  
Exercisable, Aggregate Intrinsic Value $ 45,458