Leases - Supplemental Income Statement Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2023	Feb. 28, 2022
Operating lease cost
Fixed	$ 853	$ 815	$ 1,667	$ 1,619
Variable	203	197	395	402
Finance lease cost
Amortization	11	11	21	22
Interest	12	13	24	26
Sublease income	28	26	57	51
Impairment of right-of-use assets	4	3	71	71
Gain on sale and leaseback	343	148	532	235
U.S. Retail Pharmacy
Finance lease cost
Gain on sale and leaseback	211	148	384	235
International
Finance lease cost
Gain on sale and leaseback	132	$ 0	148	$ 0
International \| GERMANY
Finance lease cost
Gain on sale and leaseback	132		148
International \| GERMANY \| Fiscal Year 2023 Acquistions
Finance lease cost
Gain on sale and leaseback	$ 24		$ 41

Amount of interest expense on finance lease liability.

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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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Operating Lease, Cost

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