Share-Based Compensation (Share-Based Compensation Arrangement Expenses Recognized) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Salaries, wages and employee benefits	$ 6,031	$ 5,062
Deferred income tax benefit	(2,347)	(1,965)
Net share-based compensation expense	$ 3,684	$ 3,097

Employee Service Share Based Compensation Deferred Tax Benefit From Compensation Expense

No definition available.

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Period Type:	duration