Exit and disposal activities - restructuring reserve activity (Details) - Transformational cost management program - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2023	Aug. 31, 2022
Restructuring Reserve [Roll Forward]
Beginning balance	$ 113	$ 114
Costs	1,158	690
Payments	(320)	(323)
Other - non cash	(849)	(367)
Ending balance	102	113
Lease obligations and other real estate costs
Restructuring Reserve [Roll Forward]
Beginning balance	10	17
Costs	516	249
Payments	(105)	(99)
Other - non cash	(411)	(157)
Ending balance	10	10
Asset impairments
Restructuring Reserve [Roll Forward]
Beginning balance	0	0
Costs	441	190
Payments	0	0
Other - non cash	(441)	(190)
Ending balance	0	0
Employee severance and business transition costs
Restructuring Reserve [Roll Forward]
Beginning balance	76	77
Costs	150	210
Payments	(160)	(201)
Other - non cash	2	(9)
Ending balance	70	76
Information technology transformation and other exit costs
Restructuring Reserve [Roll Forward]
Beginning balance	27	20
Costs	51	40
Payments	(55)	(23)
Other - non cash	0	(11)
Ending balance	$ 22	$ 27