Share-Based Compensation (Summary Of Stock Option Activity) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012 Y	Jun. 30, 2012 Y	Jun. 30, 2011
Share-based Compensation [Abstract]
Shares, Beginning Balance		2,286
Shares, Granted	310
Shares, Exercised	(224)
Shares, Forfeited	(28)	0
Shares, Ending Balance	2,344	2,344
Shares, Exercisable	1,519	1,519
Shares, Vested and expected to vest	2,314	2,314
Weighted Average Exercise Price, Beginning Balance (in $/share)		$ 30.11
Weighted Average Exercise Price, Granted (in $/share)	$ 32.97	$ 32.97
Weighted Average Exercise Price, Exercised (in $/share)	$ 21.56	$ 21.56
Weighted Average Exercise Price, Forfeited (in $/share)	$ 29.80	$ 29.80	$ 0.00
Weighted Average Exercise Price, Ending Balance (in $/share)	$ 31.31	$ 31.31
Weighted Average Exercise Price, Exercisable (in $/share)	$ 33.35	$ 33.35
Weighted Average Exercise Price, Vested and expected to vest (in $/share)	$ 31.31	$ 31.31
Weighted Average Remaining Life, Ending Balance (in years)	5.5	5.5
Weighted Average Remaining Life, Exercisable (in years)	4.1
Weighted Average Remaining Life, Vested and expected to vest (in years)	5.5
Aggregate Intrinsic Value, Ending Balance	$ 20,774	$ 20,774
Aggregate Intrinsic Value, Exercisable	13,619	13,619
Aggregate Intrinsic Value, Vested and expected to vest	$ 20,617	$ 20,617