XML 78 R62.htm IDEA: XBRL DOCUMENT v3.8.0.1
Share-Based Compensation Expense (Detail) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense $ 13,293 $ 12,319 $ 12,596
Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense 1,451 1,149 952
Non-Vested Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense $ 11,842 $ 11,170 $ 11,644