Compensation and Benefit Plans (Black-Sholes Option Pricing Model Assumptions) (Details) (Employee Stock Option)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected terms (in years)	6 years 10 months 24 days	7 years	7 years 3 months 18 days
Weighted-average expected dividend yield	3.00%	3.40%	3.80%
Weighted-average volatility	18.30%	18.90%	19.80%
Risk-free interest rate, maximum	1.70%	3.10%	3.20%
Risk-free interest rate, minimum	1.10%	1.40%	2.00%
Expected dividend yield, maximum	3.10%	3.50%	4.00%
Expected dividend yield, minimum	2.80%	3.10%	3.30%
Expected volatility, maximum	18.30%	19.00%	19.80%
Expected volatility, minimum	17.40%	18.20%	18.80%