FAIR VALUE MEASUREMENTS Narrative (Details) - USD ($) $ in Millions	May 31, 2020	May 31, 2019
Marketable security investments maturity information [Abstract]
Total debt, carrying value	$ 71,807	$ 56,342
Senior notes [Member]
Marketable security investments maturity information [Abstract]
Total debt, carrying value	71,600	56,100
Fair Value Measurements Using Input Types Level 2 [Member] \| Senior notes [Member]
Marketable security investments maturity information [Abstract]
Total debt, fair value	$ 80,900	$ 58,400

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant