FAIR VALUE MEASUREMENTS - Notional Amount of Foreign Currency Exchange Derivatives (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Recurring Basis
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Assets at fair value	$ 12,663	$ 10,751
Recurring Basis \| Level 2
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Assets at fair value	504	2,945
Recurring Basis \| Not Designated as Hedging Instrument \| Foreign Currency Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Assets at fair value	4	12
Liabilities at fair value	3	5
Recurring Basis \| Not Designated as Hedging Instrument \| Level 2 \| Foreign Currency Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Assets at fair value	4	12
Liabilities at fair value	3	5
Foreign currency purchases \| Not Designated as Hedging Instrument \| Foreign Currency Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	1,050	1,770
Foreign currency sales \| Not Designated as Hedging Instrument \| Foreign Currency Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 636	$ 901

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Nominal or face amount used to calculate payment on derivative.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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