Financial Instruments - Fair Value of Derivative Financial Instruments and Related Notional Amounts (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Derivative asset	$ 992	$ 1,140
Derivative liability	718	1,024
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative asset	909	1,085
Derivative liability	662	968
Foreign exchange contracts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	25,193	22,984
Derivative asset	591	654
Derivative liability	662	586
Foreign exchange contracts [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	19,623	15,154
Derivative asset	82	55
Derivative liability	55	55
Interest rate contracts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	6,645	11,145
Derivative asset	318	432
Derivative liability	0	383
Sales [Member] \| Foreign exchange contracts [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative, notional amount	$ 5,900	$ 5,800

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 20
-Section 55
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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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.

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No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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