FINANCIAL INSTRUMENTS - Net Investment Hedges (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative [Line Items]
Gain (loss) recognized in AOCI on hedging instruments	$ 158	$ (68)
Reclassified from AOCI into earnings	0	6
Net investment hedges
Derivative [Line Items]
Gain (loss) excluded from assessment recognized in earnings	2	8
Currency exchange contracts
Derivative [Line Items]
Gain (loss) recognized in AOCI on hedging instruments	109	(27)
Foreign currency debt
Derivative [Line Items]
Gain (loss) recognized in AOCI on hedging instruments	48	(41)
Carrying value designated as net investment hedges	$ 9,145	$ 12,502

Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109974929&loc=SL110061172-113977

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Fair value of all derivative liabilities designated as hedges of net investment in foreign operations.

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Amount, before tax and reclassification, of gain (loss) from derivative designated and qualifying as net investment hedge.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from derivative designated and qualifying as net investment hedge.

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