Postretirement Plans (Schedule Of Changes In The Benefit Obligation, Plan Assets And Funded Status Of Both Pensions And OPB) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Accrued pension plan liability, net	$ (19,943)	$ (17,783)
Pension Plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	74,388	78,391
Service cost	604	1,764	$ 1,661
Interest cost	3,050	2,990	3,058
Plan participants’ contributions	1	5
Amendments	6	(1,379)
Actuarial (gain)/loss	2,669	(3,505)
Settlement/curtailment/other	(63)	(457)
Gross benefits paid	(3,903)	(3,382)
Exchange rate adjustment	(7)	(39)
Ending balance	76,745	74,388	78,391
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance at fair value	56,514	61,119
Actual return/(loss) on plan assets	3,885	(701)
Company contribution	113	59
Plan participants’ contributions	1	5
Settlement payments	(24)	(649)
Benefits paid	(3,791)	(3,284)
Exchange rate adjustment	(6)	(35)
Ending balance at fair value	56,692	56,514	61,119
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Other assets	3	10
Other accrued liabilities	(113)	(101)
Accrued pension plan liability, net	(19,943)	(17,783)
Net amount recognized	(20,053)	(17,874)
Other Postretirement Benefits Plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	7,138	7,306
Service cost	128	140	129
Interest cost	262	248	289
Plan participants’ contributions	7	5
Amendments	(57)	(19)
Actuarial (gain)/loss	(612)	(89)
Settlement/curtailment/other		10
Gross benefits paid	(469)	(486)
Subsidies	37	43
Exchange rate adjustment	4	(15)
Ending balance	6,431	7,138	7,306
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Beginning balance at fair value	132	141
Actual return/(loss) on plan assets	7	1
Company contribution	6	5
Plan participants’ contributions	7	5
Benefits paid	(18)	(20)
Ending balance at fair value	134	132	$ 141
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Other accrued liabilities	(381)	(390)
Accrued retiree health care	(5,916)	(6,616)
Net amount recognized	$ (6,297)	$ (7,006)