Pension And Postretirement Benefits (Pension And Postretirement Benefit Costs Included In Operating Expenses) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Net (credit) cost	$ (33)	$ 130
Pension Benefit Cost [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the period	282	330
Interest cost on benefit obligation	661	607
Expected return on assets	(849)	(828)
Amortization of prior service (credit)	(24)	(23)
Net (credit) cost	70	86
Postretirement Benefit Cost [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the period	58	95
Interest cost on benefit obligation	365	390
Expected return on assets	(164)	(178)
Amortization of prior service (credit)	(362)	(263)
Net (credit) cost	$ (103)	$ 44