Share-based Compensation - Summary of Additional Restricted Stock Information (Detail) - Restricted Stock [Member] - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
Weighted-average grant date fair value per share | $ 16.37 | $ 15.36 | $ 16.23 |
Fair value of restricted stock awards that vested | $ 347 | $ 2,198 | $ 224 |