Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Restricted Stock Units - Additional Information (Detail)

v3.8.0.1
Stock-Based Compensation - Restricted Stock Units - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Unrecognized stock-based compensation expense, expected recognition weighted-average period 4 years 3 months 19 days  
Restricted Stock Units [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Weighted-average grant date fair value, Granted $ 23.39  
Number of restricted stock units granted 26,625 0
Total fair value vested $ 0 $ 0
Unrecognized stock-based compensation expense related to restricted stock units $ 5,300  
Unrecognized stock-based compensation expense, expected recognition weighted-average period 4 years 8 months 12 days