Share-Based Compensation (Share-Based Compensation Arrangement Expenses Recognized) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Salaries, wages and employee benefits	$ 5,163	$ 4,767	$ 11,194	$ 9,829
Deferred income tax benefit	(2,010)	(1,853)	(4,357)	(3,818)
Net share-based compensation expense	$ 3,153	$ 2,914	$ 6,837	$ 6,011

Employee Service Share Based Compensation Deferred Tax Benefit From Compensation Expense

No definition available.

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