Stock-Based Compensation (Number Of Shares At Average Grant Date Fair Value Over Ten Day Period Table) (Details) (Performance Shares [Member], USD $)	12 Months Ended
	Dec. 31, 2012
Incentive Plan, 2010-2012 [Member] | Ten Day Period - February 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Average Ten Day Grant Date Fair Value	$ 29.39
Incentive Plan, 2011-2013 [Member] | Ten Day Period - February 2011 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Average Ten Day Grant Date Fair Value	$ 40.25
Incentive Plan, 2012-2014 [Member] | Ten Day Period - February 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Average Ten Day Grant Date Fair Value	$ 31.60