Leases - supplemental income statement information (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2023	Aug. 31, 2022	Aug. 31, 2021
Operating lease cost
Fixed	$ 3,404	$ 3,240	$ 3,219
Variable	850	825	664
Finance lease cost
Amortization	47	44	45
Interest	51	50	52
Sublease income	115	105	84
Impairment of right-of-use assets	495	218	86
Gain on sale-leaseback transactions	925	619	367
U.S. Retail Pharmacy
Finance lease cost
Gain on sale-leaseback transactions	747	558	367
International
Finance lease cost
Gain on sale-leaseback transactions	178	61	$ 0
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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