Risk Management and Derivatives - Effects Of Cash Flow Hedges in Statement of Income (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2020	May 31, 2019	May 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Revenues	$ 37,403	$ 39,117	$ 36,397
Cost of sales	21,162	21,643	20,441
Demand creation expense	3,592	3,753	3,577
Other (income) expense, net	139	(78)	66
Interest expense (income), net	89	49	54
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	519	76	(131)
Foreign exchange forwards and options | Revenue | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(17)	(5)	34
Foreign exchange forwards and options | Cost of sales | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	364	53	(90)
Foreign exchange forwards and options | Demand creation expense | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	(2)	0	1
Foreign exchange forwards and options | Other (income) expense, net | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	181	35	(69)
Interest rate swaps | Interest (income) expense, net | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax	$ (7)	$ (7)	$ (7)