Stock-Based Compensation (Stock Option Weighted-Average Assumptions Used In Determining Fair Values) (Details)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation [Abstract]
Stock price volatility	25.11%	24.25%	25.73%
Expected term	6 years 6 months 20 days	6 years 7 months 21 days	5 years 5 months 16 days
Risk-free interest rate	1.22%	2.70%	2.57%
Dividend yield	4.50%	4.20%	3.74%
Dividend payment per share	3.32	3.32	3.24