Stock-Based Compensation (Schedule Of Restricted Stock Awards) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted (in shares)	686
Weighted-average grant date fair value (in dollars per share)	$ 53.32
Time Based Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted (in shares)	428
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted (in shares)	172	[1]
Market Based Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted (in shares)	86	[1]

[1] *Assumes target payout