DERIVATIVE FINANCIAL INSTRUMENTS EFFECTS ON EARNINGS AND AOCL (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 31, 2020	Aug. 31, 2019
Derivative [Line Items]
Non-operating (expenses) income, net	$ (2)	$ 99
Interest expense	(614)	(494)
Cash flow hedges [Member] \| Cross-Currency Swap Agreements [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Cross-currency swap agreements designated as cash flow hedges	108	(32)
Non-Operating (Expenses) Income, Net [Member]
Derivative [Line Items]
Non-operating (expenses) income, net	(2)	99
Effects of derivative instruments designated as hedges on income [Abstract]:
Total gain (loss) on hedges recognized in income	112	(11)
Non-Operating (Expenses) Income, Net [Member] \| Fair value hedges [Member] \| Interest Rate Swaps [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	0	0
Hedged items	0	0
Non-Operating (Expenses) Income, Net [Member] \| Fair value hedges [Member] \| Cross-currency interest rate swap agreements [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	72	(18)
Hedged items	(63)	15
Non-Operating (Expenses) Income, Net [Member] \| Cash flow hedges [Member] \| Cross-Currency Swaps [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Amount of gain (loss) reclassified from accumulated OCI	103	(8)
Interest Expense [Member]
Derivative [Line Items]
Interest expense	(614)	(494)
Effects of derivative instruments designated as hedges on income [Abstract]:
Total gain (loss) on hedges recognized in income	0	0
Interest Expense [Member] \| Fair value hedges [Member] \| Interest Rate Swaps [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	(5)	16
Hedged items	5	(16)
Interest Expense [Member] \| Fair value hedges [Member] \| Cross-currency interest rate swap agreements [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	2	23
Hedged items	(2)	(23)
Interest Expense [Member] \| Cash flow hedges [Member] \| Cross-Currency Swaps [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Amount of gain (loss) reclassified from accumulated OCI	$ 0	$ 0

Nonoperating income expense including elimination of net income loss attributable to noncontrolling interests.

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

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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