Accumulated Other Comprehensive Income (Loss) (Details 2) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Other income (expense)		$ 64	$ 28	$ 88	$ 112
Interest expense excluding Financial Products		(118)	(126)	(362)	(385)
Interest expense of Financial Products		(163)	(147)	(484)	(447)
Reclassifications before tax		1,523	383	2,971	1,487
Tax (provision) benefit		(470)	(96)	(921)	(372)
Reclassifications net of tax	[1]	1,059	283	2,053	1,104
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Reclassifications net of tax		6	(3)	(57)	24
Reclassification out of Accumulated Other Comprehensive Income | Foreign currency translation
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Other income (expense)		(11)	(13)	(13)	(13)
Tax (provision) benefit		0	0	0	0
Reclassifications net of tax		(11)	(13)	(13)	(13)
Reclassification out of Accumulated Other Comprehensive Income | Pension and other postretirement benefits
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Amortization of prior service credit (cost)		6	15	18	45
Tax (provision) benefit		(2)	(5)	(6)	(16)
Reclassifications net of tax		4	10	12	29
Reclassification out of Accumulated Other Comprehensive Income | Derivative financial instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Reclassifications before tax		(16)	(8)	(118)	(24)
Tax (provision) benefit		5	2	41	8
Reclassifications net of tax		(11)	(6)	(77)	(16)
Reclassification out of Accumulated Other Comprehensive Income | Derivative financial instruments | Foreign exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Other income (expense)		(16)	(6)	(118)	(16)
Reclassification out of Accumulated Other Comprehensive Income | Derivative financial instruments | Interest rate contracts | Machinery, Energy & Transportation
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Interest expense excluding Financial Products		(2)	(2)	(5)	(5)
Reclassification out of Accumulated Other Comprehensive Income | Derivative financial instruments | Interest rate contracts | Financial Products
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Interest expense of Financial Products		2	0	5	(3)
Reclassification out of Accumulated Other Comprehensive Income | Available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income
Other income (expense)		36	9	32	36
Tax (provision) benefit		(12)	(3)	(11)	(12)
Reclassifications net of tax		$ 24	$ 6	$ 21	$ 24

[1] 1 Profit attributable to common shareholders.