Stock-Based Compensation (Schedule Of Restricted Stock Awards) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted, Shares	562
Weighted-Average Grant Date Fair Value (per share)	$ 48.67
Time-Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted, Shares	368
Performance-Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted, Shares	129	[1]
Market-Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock granted, Shares	65	[1]

[1] *Assumes target payout