Risk Management and Derivatives - Effects Of Cash Flow Hedges in Statement of Income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Revenues	$ 9,374	$ 8,554	$ 19,322	$ 17,624
Cost of sales	5,269	4,876	10,820	9,984
Demand creation expense	910	877	1,874	1,732
Other (income) expense, net	(48)	18	5	36
Interest expense (income), net	14	13	25	29
Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on cash flow hedge activity	12	(30)	(38)	17
Foreign exchange forwards and options | Revenues | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on cash flow hedge activity	3	13	8	15
Foreign exchange forwards and options | Cost of sales | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on cash flow hedge activity	10	(21)	(34)	24
Foreign exchange forwards and options | Other (income) expense, net | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on cash flow hedge activity	0	(20)	(9)	(18)
Interest rate swaps | Interest expense (income), net | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on cash flow hedge activity	$ (1)	$ (2)	$ (3)	$ (4)