Stock compensation plans (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2022	Aug. 31, 2021	Aug. 31, 2020
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	$ 391	$ 155	$ 137
Unrecognized compensation cost related to non-vested awards	$ 399
Compensation cost not yet recognized period for recognition	3 years
2021 Omnibus Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	$ 133	$ 155	$ 137
Walgreens health
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total stock-based compensation expense	$ 269

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of noncash expense for share-based payment arrangement.

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