Employee Benefit Plans (Assumptions To Determine The Fair Value Of Options Granted) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Employee Benefit Plans [Abstract]
Risk-free interest rate, minimum	0.01%	0.14%	0.08%
Risk-free interest rate, maximum	3.91%	4.98%	5.21%
Weighted-average risk-free interest rate	2.23%	2.79%	3.50%
Dividend yield	2.84%	2.79%	2.74%
Expected market price volatility, minimum	24.87%	31.11%	31.16%
Expected market price volatility, maximum	31.32%	41.40%	52.70%
Weighted-average expected market price volatility	29.43%	34.65%	39.25%
Expected term, minimum years	6.0	5.6	5.7
Expected term, maximum years	7.0	6.9	6.8
Weighted-average expected term, Years	6.3	6.0	6.3