Leases - supplemental balance sheet information (Details) - USD ($) $ in Millions	Aug. 31, 2024	Aug. 31, 2023
Operating leases:
Operating lease right-of-use assets	$ 20,335	$ 21,667
Operating lease obligations - current	2,382	2,347
Operating lease obligations - non-current	20,921	22,124
Total operating lease obligations	23,303	24,472
Finance leases:
Property, plant and equipment, net	680	678
Lease obligations included in:
Accrued expenses and other liabilities	74	57
Other non-current liabilities	917	919
Total finance lease obligations	$ 991	$ 976
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization	Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued expenses and other liabilities	Accrued expenses and other liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other non-current liabilities	Other non-current liabilities