Shareowners' Equity and Noncontrolling Interest (Summary of Changes in AOCI) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (7,729)	$ (7,388)	$ (7,729)	$ (7,388)	$ (7,484)	$ (7,619)	$ (6,577)	$ (6,661)
Other comprehensive (loss) income before reclassifications, net - Foreign Currency Translation	(359)	(936)	(596)	(1,202)
Amounts reclassified, pretax - Foreign Currency Translation	1	0	0	1
Tax reclassified - Foreign Currency Translation	0	0	0	0
Other comprehensive (loss) income before reclassifications, net - Pension	(4)	(73)	21	(104)
Amounts reclassified, pretax - Pension	127	216	381	651
Tax reclassified - Pension	47	81	140	243
Other comprehensive (loss) income before reclassifications, net - AFS Securities	30	(48)	87	10
Amounts reclassified, pretax - AFS Securities	20	2	72	56
Tax reclassified - AFS Securities	8	7	27	25
Other comprehensive (loss) income before reclassifications, net - Unrealized Hedging (Losses) Gains	(5)	(111)	138	(194)
Amounts reclassified, pretax - Unrealized Hedging (Losses) Gains	(32)	(64)	(139)	(164)
Tax reclassified - Unrealized Hedging (Losses) Gains	(9)	(16)	(37)	(48)
Other comprehensive (loss) income before reclassifications, net	(335)	(999)	(408)	(1,219)
Amounts reclassified, pretax	(138)	(278)	(448)	(758)
Tax reclassified	(48)	(90)	(150)	(266)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(3,050)	(2,191)	(3,050)	(2,191)	(2,685)	(2,438)	(1,278)	(1,051)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(4,915)	(5,197)	(4,915)	(5,197)	(4,999)	(5,135)	(5,405)	(5,709)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	335	287	335	287	317	293	330	308
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(99)	(287)	(99)	(287)	$ (117)	$ (339)	$ (224)	$ (209)
Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive (loss) income before reclassifications, net - Foreign Currency Translation	$ (364)	$ (913)	$ (612)	$ (1,139)