Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Feb. 28, 2021	Aug. 31, 2020
Operating Leases:
Operating lease right-of-use assets	$ 21,908	$ 21,453
Operating lease obligations - current	2,360	2,358
Operating lease obligations - non-current	22,134	21,765
Total operating lease obligations	24,494	24,123
Finance Leases:
Property, plant and equipment, net	750	766
Lease obligations included in:
Accrued expenses and other liabilities	27	31
Other non-current liabilities	1,007	1,013
Total finance lease obligations	$ 1,034	$ 1,044
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Property, plant and equipment, net	Property, plant and equipment, net
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