Leases - other supplemental information (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2024	Aug. 31, 2023	Aug. 31, 2022
Cash paid for amounts included in the measurement of lease obligations
Operating cash flows from operating leases	$ 3,684	$ 3,579	$ 3,351
Operating cash flows from finance leases	51	47	47
Financing cash flows from finance leases	71	52	43
Total	3,807	3,679	3,441
Right-of-use assets obtained in exchange for new lease obligations
Operating leases	1,457	2,323	2,078
Finance leases	80	30	11
Total	$ 1,536	$ 2,352	$ 2,089