Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Share-Based Compensation Expense and Related Tax Benefits (Detail)

v2.4.0.6
Share-Based Compensation - Share-Based Compensation Expense and Related Tax Benefits (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-Based Compensation Expense $ 478 $ 608 $ 1,013
Related Tax Benefits $ 201 $ 256 $ 426