Goodwill and other intangible assets - Schedule of Goodwill (Details) $ in Millions	9 Months Ended
May 31, 2022 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 12,421
Acquisitions	9,586
Currency translation adjustments	(106)
Goodwill, ending balance	21,901
Reportable Segments \| United States
Goodwill [Roll Forward]
Goodwill, beginning balance	10,947
Acquisitions	0
Currency translation adjustments	0
Goodwill, ending balance	10,947
Reportable Segments \| International
Goodwill [Roll Forward]
Goodwill, beginning balance	1,474
Acquisitions	0
Currency translation adjustments	(106)
Goodwill, ending balance	1,368
Reportable Segments \| Walgreens Health
Goodwill [Roll Forward]
Goodwill, beginning balance	0
Acquisitions	9,586
Currency translation adjustments	0
Goodwill, ending balance	$ 9,586

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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