Leases - Supplemental Income Statement Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Operating lease cost
Fixed	$ 818	$ 820	$ 1,606	$ 1,631
Variable	159	206	319	424
Finance lease cost
Amortization	11	10	22	18
Interest	13	13	26	27
Sublease income	21	16	41	31
Gains on sale-leaseback transactions	$ 95	$ 63	$ 187	$ 140

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 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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