Share-Based Compensation (Share-Based Compensation Arrangement Expenses Recognized) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share-Based Compensation [Abstract]
Salaries, wages and employee benefits	$ 12,764	$ 15,020	$ 11,090
Deferred income tax benefit	(4,935)	(5,803)	(4,262)
Net share-based compensation expense	$ 7,829	$ 9,217	$ 6,828

Employee Service Share Based Compensation Deferred Tax Benefit From Compensation Expense

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration