Leases - future lease payments for operating and finance leases (Details) - USD ($) $ in Millions	Aug. 31, 2020	Sep. 01, 2019
Finance lease
2021	$ 96
2022	94
2023	93
2024	93
2025	91
Later	1,230
Total undiscounted minimum lease payments	1,697
Less: Present value discount	(643)
Lease liability	1,054
Operating lease
2021	3,529
2022	3,374
2023	3,210
2024	3,049
2025	2,868
Later	15,559
Total undiscounted minimum lease payments	31,589
Less: Present value discount	(7,190)
Operating lease liability	$ 24,399	$ 24,000