Leases - Future Lease Payments for Operating and Finance Leases (Details) - USD ($) $ in Millions	May 31, 2021	Aug. 31, 2020
Finance lease
2021 (Remaining period)	$ 23
2022	92
2023	91
2024	92
2025	90
2026	90
Later	1,194
Total undiscounted minimum lease payments	1,672
Less: Present value discount	(647)
Lease liability	1,025	$ 1,044
Operating lease
2021 (Remaining period)	867
2022	3,403
2023	3,296
2024	3,169
2025	3,039
2026	2,911
Later	14,569
Total undiscounted minimum lease payments	31,254
Less: Present value discount	(6,838)
Lease liability	$ 24,416	$ 24,123