Quarterly report pursuant to Section 13 or 15(d)

Summary of Compensation Expense under Share-Based Payment Arrangements and Related Tax Benefit (Detail)

v2.4.0.8
Summary of Compensation Expense under Share-Based Payment Arrangements and Related Tax Benefit (Detail) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Sep. 30, 2013
Sep. 30, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share-based compensation $ 3,507 $ 3,319 $ 8,457 $ 9,137
Tax benefit computed at the statutory rate 1,227 1,162 2,960 3,198
Restricted Stock
       
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share-based compensation 99 110 297 324
Restricted Stock Units (RSUs)
       
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share-based compensation $ 3,408 $ 3,209 $ 8,160 $ 8,813