Benefit Plans (Net Pension Liability Recognized In Consolidated Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Accrued pension costs	$ (1,735)	$ (1,662)
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Other accrued liabilities	(22)	(28)
Accrued pension costs	(1,735)	(1,662)
Net pension liability recognized at December 31	$ (1,757)	$ (1,690)