DERIVATIVE FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2017	May 31, 2016	May 31, 2015
Fair Values of Derivative and Non-Derivative Instruments Designated as Hedges in Consolidated Balance Sheets [Abstract]
Fair value, assets	$ 40	$ 122
Fair value, liabilities	(191)	(218)
Interest rate swap agreements [Member] \| Interest expense [Member]
Effects of Derivative and Non-Derivative Instruments Designated as Hedges on Income and Other Comprehensive Income (OCI) or Loss (OCL) [Abstract]
Amount of Gain (Loss) Recognized in Income on Derivative	(82)	48	$ 51
Amount of Gain (Loss) on Hedged Item Recognized in Income Attributable to Risk Being Hedged	82	(48)	(51)
Fair value hedges [Member] \| Interest rate swap agreements [Member] \| Other assets [Member]
Fair Values of Derivative and Non-Derivative Instruments Designated as Hedges in Consolidated Balance Sheets [Abstract]
Fair value, assets	40	122
Cash flow hedges [Member] \| Cross-currency swap agreements [Member]
Effects of Derivative and Non-Derivative Instruments Designated as Hedges on Income and Other Comprehensive Income (OCI) or Loss (OCL) [Abstract]
Amount of Gain (Loss) Recognized in Accumulated OCI or OCL (Effective Portion)	27	26	(318)
Cash flow hedges [Member] \| Cross-currency swap agreements [Member] \| Non-operating income (expense), net [Member]
Effects of Derivative and Non-Derivative Instruments Designated as Hedges on Income and Other Comprehensive Income (OCI) or Loss (OCL) [Abstract]
Amount of Gain (Loss) Reclassified from Accumulated OCI or OCL into Income (Effective Portion)	2	41	(348)
Cash flow hedges [Member] \| Cross-currency swap agreements [Member] \| Other non-current liabilities [Member]
Fair Values of Derivative and Non-Derivative Instruments Designated as Hedges in Consolidated Balance Sheets [Abstract]
Fair value, liabilities	(191)	(218)
Net investment hedge [Member] \| Foreign currency borrowings [Member]
Effects of Derivative and Non-Derivative Instruments Designated as Hedges on Income and Other Comprehensive Income (OCI) or Loss (OCL) [Abstract]
Amount of Gain (Loss) Recognized in Accumulated OCI or OCL (Effective Portion)	(1)	(25)	208
Amount of Gain (Loss) Reclassified from Accumulated OCI or OCL into Income (Effective Portion)	0	0	$ 0
Net investment hedge [Member] \| Foreign currency borrowings [Member] \| Notes payable, non-current [Member]
Fair Values of Derivative and Non-Derivative Instruments Designated as Hedges in Consolidated Balance Sheets [Abstract]
Fair value, debt	$ (980)	$ (991)

Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
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Fair value, before 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 elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Fair value, before 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 elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 3
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 4B
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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
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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

Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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