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Derivative Financial Instruments and Risk Management (Details 2) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Derivatives Fair Value
Asset Fair Value	$ 82		$ 74
Liability Fair Value	(126)		(93)
Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	65		52
Liability Fair Value	(10)		(25)
Financial Products
Derivatives Fair Value
Asset Fair Value	17		22
Liability Fair Value	(116)		(68)
Designated Derivatives
Derivatives Fair Value
Asset (Liability) Fair Value	(61)		(53)
Designated Derivatives \| Foreign exchange contracts \| Receivables-trade and other \| Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	24		8
Designated Derivatives \| Foreign exchange contracts \| Long-term receivables-trade and other \| Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	13		4
Designated Derivatives \| Foreign exchange contracts \| Long-term receivables-trade and other \| Financial Products
Derivatives Fair Value
Asset Fair Value	1		7
Designated Derivatives \| Foreign exchange contracts \| Accrued Expenses \| Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	(4)		(14)
Designated Derivatives \| Foreign exchange contracts \| Accrued Expenses \| Financial Products
Derivatives Fair Value
Liability Fair Value	(94)		(57)
Designated Derivatives \| Foreign exchange contracts \| Other Liabilities \| Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	0		(2)
Designated Derivatives \| Interest rate contracts \| Long-term receivables-trade and other \| Financial Products
Derivatives Fair Value
Asset Fair Value	2		3
Designated Derivatives \| Interest rate contracts \| Accrued Expenses \| Financial Products
Derivatives Fair Value
Liability Fair Value	(3)		(2)
Undesignated Derivatives
Derivatives Fair Value
Asset (Liability) Fair Value	17		34
Undesignated Derivatives \| Foreign exchange contracts \| Receivables-trade and other \| Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	19		19
Undesignated Derivatives \| Foreign exchange contracts \| Receivables-trade and other \| Financial Products
Derivatives Fair Value
Asset Fair Value	14		12
Undesignated Derivatives \| Foreign exchange contracts \| Accrued Expenses \| Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	(3)		(9)
Undesignated Derivatives \| Foreign exchange contracts \| Accrued Expenses \| Financial Products
Derivatives Fair Value
Liability Fair Value	(19)		(9)
Undesignated Derivatives \| Commodity contracts \| Receivables-trade and other \| Machinery, Energy & Transportation
Derivatives Fair Value
Asset Fair Value	9		21
Undesignated Derivatives \| Commodity contracts \| Accrued Expenses \| Machinery, Energy & Transportation
Derivatives Fair Value
Liability Fair Value	(3)		0
Cash Flow Hedges \| Designated Derivatives
Derivatives Fair Value
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	6	$ 15
Amount of Gains (Losses) Reclassified from AOCI to Earnings	(24)	(62)
Recognized in Earnings (Ineffective Portion)	0	0
Cash Flow Hedges \| Designated Derivatives \| Foreign exchange contracts \| Machinery, Energy & Transportation
Derivatives Fair Value
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	39	33
Cash Flow Hedges \| Designated Derivatives \| Foreign exchange contracts \| Financial Products
Derivatives Fair Value
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	(33)	(18)
Cash Flow Hedges \| Designated Derivatives \| Interest rate contracts \| Machinery, Energy & Transportation
Derivatives Fair Value
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	0	0
Cash Flow Hedges \| Designated Derivatives \| Interest rate contracts \| Financial Products
Derivatives Fair Value
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	0	0
Interest Expense \| Cash Flow Hedges \| Designated Derivatives \| Foreign exchange contracts \| Financial Products
Derivatives Fair Value
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)			$ 0
Amount of Gains (Losses) Reclassified from AOCI to Earnings	3
Recognized in Earnings (Ineffective Portion)	0
Interest Expense \| Cash Flow Hedges \| Designated Derivatives \| Interest rate contracts \| Machinery, Energy & Transportation
Derivatives Fair Value
Amount of Gains (Losses) Reclassified from AOCI to Earnings	0	(2)
Recognized in Earnings (Ineffective Portion)	0	0
Interest Expense \| Cash Flow Hedges \| Designated Derivatives \| Interest rate contracts \| Financial Products
Derivatives Fair Value
Amount of Gains (Losses) Reclassified from AOCI to Earnings	1	1
Recognized in Earnings (Ineffective Portion)	$ 0	$ 0