Stock Compensation Plans (Stock-Based Compensation Expense Included In Consolidated Statement Of Income) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 23,591	$ 22,001	$ 19,652
Less tax benefit	(7,730)	(8,028)	(7,102)
Total stock-based compensation, net of tax	15,861	13,973	12,550
Equity-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	20,547	18,382	17,449
Liability-Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation	$ 3,044	$ 3,619	$ 2,203