The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and other intangible assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020	Aug. 31, 2020	Jun. 01, 2020
Goodwill [Line Items]
Goodwill	$ 12,468		$ 12,468		$ 12,013
Indefinite-lived intangible assets	7,753		7,753		$ 7,231
Amortization of intangible assets	114	$ 98	208	$ 197
Minimum
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)						4.00%
Maximum
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)						239.00%
Other International Reporting Unit
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)						4.00%
Goodwill	400		400
Boots Reporting Unit
Goodwill [Line Items]
Goodwill	1,100		1,100
Indefinite-lived intangible assets	$ 7,600		$ 7,600
Boots Reporting Unit \| Minimum
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)	4.00%		4.00%
Boots Reporting Unit \| Maximum
Goodwill [Line Items]
Reporting unit fair value in excess of carrying amount (as a percent)	31.00%		31.00%