Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 29, 2020	Feb. 29, 2020
Leases [Abstract]
Gains on sale-leaseback transactions	$ 63	$ 140
Cash paid for amounts included in the measurement of lease obligations
Operating cash flows from operating leases		1,677
Operating cash flows from finance leases		24
Financing cash flows from finance leases		23
Total		1,724
Right-of-use assets obtained in exchange for new lease obligations:
Operating leases		1,313
Finance leases		65
Total		$ 1,378

Amount of interest paid on finance lease liability.

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Amount of cash outflow for principal payment on finance lease.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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Amount of increase in right-of-use asset obtained in exchange for operating 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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Cash Flow, Lessee

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Leases, Payments

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