Stock-Based Compensation (Schedule Of Weighted Average Value And Assumptions For Fair Value Of Options) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value	$ 23.39	$ 19.22	$ 8.31
Risk-free interest rate	1.00%	2.80%	2.90%
Expected life in years	5 years	6 years	6 years
Expected volatility	45.70%	41.90%	41.80%
Expected dividend yield	0.50%	0.50%	1.10%