XML 93 R79.htm IDEA: XBRL DOCUMENT v3.6.0.2
Share-based Compensation - Summary of Additional Restricted Stock Unit Information (Detail) - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Restricted Stock Units (RSUs) [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted-average grant date fair value per unit $ 17.02 $ 14.89 $ 17.76