Goodwill and other intangible assets - Schedule of Goodwill (Details) $ in Millions	3 Months Ended
Nov. 30, 2021 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 12,421
Acquisitions	9,130
Currency translation adjustments	(32)
Goodwill, ending balance	21,520
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	(32)
Goodwill, ending balance	1,443
Reportable Segments \| Walgreens Health
Goodwill [Roll Forward]
Goodwill, beginning balance	0
Acquisitions	9,130
Currency translation adjustments	0
Goodwill, ending balance	$ 9,130

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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