Leases - supplemental income statement information (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2024	Aug. 31, 2023	Aug. 31, 2022
Operating lease cost
Fixed	$ 3,473	$ 3,404	$ 3,240
Variable	909	850	825
Finance lease cost
Amortization	68	47	44
Interest	53	51	50
Sublease income	111	115	105
Impairment of right-of-use assets	526	495	218
Gain on sale-leaseback transactions	295	925	619
U.S. Retail Pharmacy
Finance lease cost
Gain on sale-leaseback transactions	295	747	558
International
Finance lease cost
Gain on sale-leaseback transactions	$ 0	178	61
International \| Germany
Finance lease cost
Gain on sale-leaseback transactions		178
International \| Germany \| Fiscal Year 2023 Acquisitions
Finance lease cost
Gain on sale-leaseback transactions		$ 47
International \| United Kingdom
Finance lease cost
Gain on sale-leaseback transactions			$ 61

Amount of interest expense on finance lease liability.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of loss from impairment of right-of-use asset from operating lease.

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Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

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Amount of sublease income excluding finance and operating lease expense.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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Lessee, Finance Lease, Cost

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Operating Lease, Cost

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