Leases - Other Supplemental Information (Details) - USD ($) $ in Millions	3 Months Ended
	Nov. 30, 2021	Nov. 30, 2020
Cash paid for amounts included in the measurement of lease obligations:
Operating cash flows from operating leases	$ 846	$ 857
Operating cash flows from finance leases	12	12
Financing cash flows from finance leases	11	10
Total	869	879
Right-of-use assets obtained in exchange for new lease obligations:
Operating leases	544	787
Finance leases	5	0
Total	$ 549	$ 787