DERIVATIVE FINANCIAL INSTRUMENTS EFFECTS ON BALANCE SHEETS (Details) - USD ($) $ in Millions	May 31, 2019	May 31, 2018
Derivative assets:
Total derivative assets	$ 5	$ 29
Derivative liabilities:
Total derivative liabilities	230	158
Fair value hedges [Member] \| Notes payable and other borrowings, current [Member]
Effects of fair value hedging relationship on hedged item in condensed consolidated balance sheet [Abstract]
Carrying amount of hedged item	1,994	1,492
Cumulative hedging adjustments included in the carrying amount	(5)	(7)
Fair value hedges [Member] \| Notes payable and other borrowings, non-current [Member]
Effects of fair value hedging relationship on hedged item in condensed consolidated balance sheet [Abstract]
Carrying amount of hedged item	3,652	5,584
Cumulative hedging adjustments included in the carrying amount	44	(19)
Fair value hedges [Member] \| Interest Rate Swaps [Member] \| Other non-current assets [Member]
Derivative assets:
Total derivative assets	5	24
Fair value hedges [Member] \| Interest Rate Swaps [Member] \| Other current liabilities [Member]
Derivative liabilities:
Total derivative liabilities	5	7
Fair value hedges [Member] \| Interest Rate Swaps [Member] \| Other non-current liabilities [Member]
Derivative liabilities:
Total derivative liabilities	0	48
Fair value hedges [Member] \| Cross-Currency Interest Rate Swaps [Member] \| Other non-current assets [Member]
Derivative assets:
Total derivative assets	0	5
Fair value hedges [Member] \| Cross-Currency Interest Rate Swaps [Member] \| Other non-current liabilities [Member]
Derivative liabilities:
Total derivative liabilities	17	0
Cash flow hedges [Member] \| Cross-Currency Swaps [Member] \| Other non-current liabilities [Member]
Derivative liabilities:
Total derivative liabilities	$ 208	$ 103

Fair value of all liability derivatives designated as cash flow hedging instruments.

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