Goodwill and other intangible assets - schedule of goodwill (Details) - USD ($) $ in Millions		12 Months Ended
Nov. 24, 2021	Aug. 31, 2022	Aug. 31, 2021
Goodwill [Roll Forward]
Beginning balance		$ 12,421	$ 12,013
Acquisitions		10,040	414
Currency translation adjustments		(181)	(7)
Ending balance		22,280	12,421
Innovation Associates, Inc.
Goodwill [Roll Forward]
Acquisitions		394
Joint Venture With McKesson
Goodwill [Roll Forward]
Acquisitions			21
VillageMD
Goodwill [Roll Forward]
Acquisitions	$ 8,041
Shields Health Solutions
Goodwill [Roll Forward]
Acquisitions		1,500
CareCentrix, Inc.
Goodwill [Roll Forward]
Acquisitions		454
Ending balance		454
Reportable Segments \| U.S. Retail Pharmacy
Goodwill [Roll Forward]
Beginning balance		10,947	10,553
Acquisitions		0	394
Currency translation adjustments		0	0
Ending balance		10,947	10,947
Reportable Segments \| International
Goodwill [Roll Forward]
Beginning balance		1,474	1,460
Acquisitions		0	21
Currency translation adjustments		(181)	(7)
Ending balance		1,293	1,474
Reportable Segments \| Walgreens health
Goodwill [Roll Forward]
Beginning balance		0	0
Acquisitions		10,040	0
Currency translation adjustments		0	0
Ending balance		$ 10,040	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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