FINANCIAL INSTRUMENTS - Fair Value Hedges (Details) $ in Millions	Mar. 31, 2019 USD ($)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cumulative amount of fair value hedging adjustments	$ 3,712
Hedged liability	58,885
Short-term borrowings
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cumulative amount of fair value hedging adjustments	40
Hedged liability	9,081
Cumulative amount of fair value hedging on discontinued hedging relationships	18
Long-term borrowings
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cumulative amount of fair value hedging adjustments	3,672
Hedged liability	49,804
Cumulative amount of fair value hedging on discontinued hedging relationships	$ 2,667

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.

No definition available.

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk, remaining after discontinued hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

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- Definition

Amount of liability hedged in fair value hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EE
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959

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