Shareowners' Equity (Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Benefit (provision) for income taxes	$ (479)	$ (799)	$ (340)	$ (7,093)
Other comprehensive income, net of tax	810	4,170	1,636	(70)
Less Other comprehensive income (loss) attributable to noncontrolling interests	3	12	6	(36)
Accumulated Other Comprehensive Income (Loss) Ending balance	(14,898)	(18,206)	(14,898)	(18,206)
Investment Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) Beginning balance	680	1,245	460	1,013
Other comprehensive income (OCI) before reclassifications - net of deferred taxes	419	(692)	578	(405)
OCI before reclassification tax	222	(365)	304	(210)
Benefit (provision) for income taxes	(9)	3	31	(26)
Reclassification from OCI net of deferred taxes	(21)	10	39	(44)
Other comprehensive income, net of tax	397	(682)	617	(449)
Less Other comprehensive income (loss) attributable to noncontrolling interests	0	1	0	0
Accumulated Other Comprehensive Income (Loss) Ending balance	1,077	564	1,077	564
Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) Beginning balance	(5,500)	(7,716)	(5,499)	(2,427)
Other comprehensive income (OCI) before reclassifications - net of deferred taxes	26	1,511	141	(3,828)
OCI before reclassification tax	(50)	(201)	217	1,343
Benefit (provision) for income taxes	(39)	(150)	80	(151)
Reclassification from OCI net of deferred taxes	29	304	(85)	307
Other comprehensive income, net of tax	55	1,815	57	(3,521)
Less Other comprehensive income (loss) attributable to noncontrolling interests	3	13	6	(34)
Accumulated Other Comprehensive Income (Loss) Ending balance	(5,448)	(5,914)	(5,448)	(5,914)
Cash Flow Hedge
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) Beginning balance	(26)	(226)	(80)	(180)
Other comprehensive income (OCI) before reclassifications - net of deferred taxes	(15)	433	(40)	(493)
OCI before reclassification tax	2	42	(5)	4
Benefit (provision) for income taxes	(4)	(68)	1	49
Reclassification from OCI net of deferred taxes	(10)	(347)	69	533
Other comprehensive income, net of tax	(25)	86	30	40
Less Other comprehensive income (loss) attributable to noncontrolling interests	0	0	0	0
Accumulated Other Comprehensive Income (Loss) Ending balance	(51)	(140)	(51)	(140)
Benefit Plans [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss) Beginning balance	(10,859)	(15,667)	(11,410)	(16,578)
Other comprehensive income, net of tax	382	2,951	933	3,860
Prior Service credit (costs)- net of deferred taxes	0	2,090	23	2,090
Net actuarial gain (loss), Tax	(65)	204	(43)	269
Net actuarial gain (loss) - net of deferred taxes	(80)	349	(12)	559
Prior service credit (costs), tax	0	1,194	5	1,194
Net curtailment/settlement, tax	0	(71)	0	(44)
Net curtailment/settlement - net of deferred taxes	(1)	(125)	(1)	(77)
Prior service cost amortization, tax	20	38	41	75
Prior service cost amortization - net of deferred taxes	17	51	33	101
Net actuarial loss amortization, tax	217	301	433	605
Net actuarial loss amortization - net of deferred taxes	447	586	890	1,187
Less Other comprehensive income (loss) attributable to noncontrolling interests	0	0	(1)	(2)
Accumulated Other Comprehensive Income (Loss) Ending balance	$ (10,476)	$ (12,716)	$ (10,476)	$ (12,716)