Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Summary of Activity of Restricted Stock Units (Detail)

v3.10.0.1
Stock-Based Compensation - Summary of Activity of Restricted Stock Units (Detail) - Restricted Stock Units [Member] - $ / shares
6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Number of restricted stock units outstanding, Unvested beginning balance 1,373,933  
Number of restricted stock units outstanding, Granted 27,875  
Number of restricted stock units outstanding, Vested (186,727)  
Number of restricted stock units outstanding, Cancelled (171,500)  
Number of restricted stock units outstanding, Unvested ending balance 1,043,581  
Weighted-average grant date fair value, Unvested beginning balance $ 8.00  
Weighted-average grant date fair value, Granted 23.03 $ 8.00
Weighted-average grant date fair value, Vested 8.00  
Weighted-average grant date fair value, Cancelled 8.00  
Weighted-average grant date fair value, Unvested ending balance $ 8.40