Derivatives - Cash Flow Hedges (Details) - Cash flow hedge - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivatives in Cash Flow Hedging Relationships
Pretax Gain (Loss) Recognized in Other Comprehensive Income on Effective portion of Derivative	$ (82)	$ (101)
Pretax gain (loss) recognized in income on effective portion of derivative as a result of reclassification from accumulated other comprehensive income	(34)	18
Accumulated other comprehensive income (loss), unrealized gain (loss) on cash flow hedges	(173)
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the income statement within next twelve months	(107)
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the Income Statement over remaining fiscal year	(82)
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the Income Statement in 2019	(57)
After-tax unrealized gain (loss) anticipated to be reclassified from AOCI to the Income Statement after 2019	$ (34)
Foreign currency forward/option contracts
Derivatives in Cash Flow Hedging Relationships
Maximum length of time hedged in cash flow hedge	36 months
Pretax Gain (Loss) Recognized in Other Comprehensive Income on Effective portion of Derivative	$ (79)	(100)
Foreign currency forward/option contracts \| Cost of sales
Derivatives in Cash Flow Hedging Relationships
Pretax gain (loss) recognized in income on effective portion of derivative as a result of reclassification from accumulated other comprehensive income	(34)	18
Interest rate swap contracts
Derivatives in Cash Flow Hedging Relationships
Derivative notional amount	200
Pretax Gain (Loss) Recognized in Other Comprehensive Income on Effective portion of Derivative	(3)	$ (1)
After-tax net unrealized gain (loss) anticipated to be reclassified from AOCI to the income statement within next twelve months	$ (9)

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

This element represents the amount of cash flow gains/losses within AOCI that will be reclassified into income for year second year after next fiscal year.

+ References

No definition available.

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- Definition

After-tax net unrealized gain (loss) anticipated to be reclassified out of AOCI one year after the next fiscal year.

+ References

No definition available.

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- Definition

After-tax net unrealized gain (loss) anticipated to be reclassified out of AOCI within the remaining fiscal year.

+ References

No definition available.

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- Definition

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80784-113994

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

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-Publisher FASB
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- Definition

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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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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