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Goodwill and other intangible assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Nov. 30, 2022	Nov. 30, 2021	Aug. 31, 2022	Jun. 01, 2022	Jun. 01, 2021
Goodwill [Line Items]
Goodwill	$ 22,582		$ 22,280
Indefinite-lived intangible assets	5,557		5,528
Amortization of intangible assets	159	$ 165
Minimum
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)				7.00%	7.00%
Maximum
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)				198.00%	18.00%
Boots Reporting Unit
Goodwill [Line Items]
Goodwill	919
Indefinite-lived intangible assets	$ 5,500		$ 5,500