Summary of Significant Accounting Policies Compensation (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	26.90%	27.40%	27.10%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years 0 months 0 days	5 years 0 months 0 days	5 years 0 months 0 days
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	4.12%	4.35%	4.56%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate	0.84%	0.71%	2.27%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 7.90	$ 8.54	$ 8.36
Historical Volatility Period Basis	10 years
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 7.97	$ 8.55	$ 8.18