Derivative Financial Instruments and Risk Management (Details 4) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Designated Derivatives \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	$ 49	$ 0	$ 55	$ 15
Amount of Gains (Losses) Reclassified from AOCI to Earnings	126	(40)	102	(102)
Recognized in Earnings (Ineffective Portion)	0	0	0	0
Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Machinery, Energy & Transportation
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	(79)	23	(40)	56
Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Machinery, Energy & Transportation \| Other Income (Expense)
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI to Earnings	4	(14)	5	(53)
Recognized in Earnings (Ineffective Portion)	0	0	0	0
Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Financial Products
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	123	(23)	90	(41)
Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Financial Products \| Other Income (Expense)
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI to Earnings	119	(27)	90	(49)
Recognized in Earnings (Ineffective Portion)	0	0	0	0
Designated Derivatives \| Cash Flow Hedges \| Foreign exchange contracts \| Financial Products \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	0		0
Amount of Gains (Losses) Reclassified from AOCI to Earnings	5		8
Recognized in Earnings (Ineffective Portion)	0		0
Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Machinery, Energy & Transportation
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	0	0	0	0
Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Machinery, Energy & Transportation \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI to Earnings	(2)	(1)	(2)	(3)
Recognized in Earnings (Ineffective Portion)	0	0	0	0
Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Financial Products
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI (Effective Portion)	5	0	5	0
Designated Derivatives \| Cash Flow Hedges \| Interest rate contracts \| Financial Products \| Interest Expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI to Earnings	0	2	1	3
Recognized in Earnings (Ineffective Portion)	0	0	0	0
Undesignated Derivatives
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	(22)	56	(22)	63
Undesignated Derivatives \| Foreign exchange contracts \| Machinery, Energy & Transportation \| Other Income (Expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	(54)	39	(38)	52
Undesignated Derivatives \| Foreign exchange contracts \| Financial Products \| Other Income (Expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	23	17	16	10
Undesignated Derivatives \| Commodity contracts \| Machinery, Energy & Transportation \| Other Income (Expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	$ 9	$ 0	$ 0	$ 1

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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