Exit and disposal activities - restructuring reserve activity (Details) - Transformational cost management program - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2022	Aug. 31, 2021
Restructuring Reserve [Roll Forward]
Beginning balance	$ 114	$ 199
Costs	690	335
Payments	(323)	(351)
Other - non cash	(367)	(69)
Ending balance	113	114
Lease obligations and other real estate costs
Restructuring Reserve [Roll Forward]
Beginning balance	17	19
Costs	249	108
Payments	(99)	(69)
Other - non cash	(157)	(42)
Ending balance	10	17
Asset impairments
Restructuring Reserve [Roll Forward]
Beginning balance	0	0
Costs	190	24
Payments	0	0
Other - non cash	(190)	(24)
Ending balance	0	0
Employee severance and business transition costs
Restructuring Reserve [Roll Forward]
Beginning balance	77	166
Costs	210	165
Payments	(201)	(252)
Other - non cash	(9)	(2)
Ending balance	76	77
Information technology transformation and other exit costs
Restructuring Reserve [Roll Forward]
Beginning balance	20	14
Costs	40	38
Payments	(23)	(31)
Other - non cash	(11)	(1)
Ending balance	$ 27	$ 20