Operating Segments and Related Information - Revenues by Major Product Line (Detail) - USD ($) $ in Millions	12 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2016
Revenue from External Customer [Line Items]
Revenues	$ 36,397	$ 34,350	$ 32,376
Footwear
Revenue from External Customer [Line Items]
Revenues	22,268	21,081	19,871
Apparel
Revenue from External Customer [Line Items]
Revenues	10,733	9,654	9,067
Equipment
Revenue from External Customer [Line Items]
Revenues	1,396	1,425	1,496
Other
Revenue from External Customer [Line Items]
Revenues	$ 2,000	$ 2,190	$ 1,942