Discontinued operations - Schedules of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2021	May 31, 2020	May 31, 2021	May 31, 2020	Aug. 31, 2020
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net earnings from discontinued operations	$ 95	$ 88	$ 289	$ 248
Disposal Group, Including Discontinued Operation, Assets, Current [Abstract]
Assets of discontinued operations - current	11,097		11,097		$ 4,979
Disposal Group, Including Discontinued Operation, Assets, Noncurrent [Abstract]
Assets of discontinued operations - non-current	0		0		4,983
Disposal Group, Including Discontinued Operation, Liabilities, Current [Abstract]
Liabilities of discontinued operations - current	6,191		6,191		5,347
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent [Abstract]
Liabilities of discontinued operations - non-current	0		0		412
Discontinued Operations, Held-for-sale | Alliance Healthcare
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Sales	5,500	4,714	16,070	14,550
Cost of sales	4,956	4,235	14,486	13,089
Gross profit	544	479	1,584	1,461
Selling, general and administrative expense	394	381	1,211	1,173
Operating income from discontinued operations	150	98	373	288
Other expense	(2)	(2)	(7)	(6)
Interest expense, net	(13)	(7)	(23)	(20)
Earnings before income tax – discontinued operations	135	89	342	262
Income tax provision	44	3	68	24
Post tax earnings from other equity method investments	4	2	15	9
Net earnings from discontinued operations	95	88	289	248
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Sales	5,500	4,714	16,070	14,550
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Cash used in operating activities - discontinued operations			(132)	(157)
Cash used for investing activities - discontinued operations			(58)	(42)
Disposal Group, Including Discontinued Operation, Assets, Current [Abstract]
Cash and cash equivalents	239		239		47
Accounts receivable, net	3,524		3,524		3,022
Inventories	1,669		1,669		1,534
Other current assets	410		410		376
Property, plant and equipment, net	943		943		0
Goodwill and intangibles	4,110		4,110		0
Other assets	202		202		0
Assets of discontinued operations - current	11,097		11,097		4,979
Disposal Group, Including Discontinued Operation, Assets, Noncurrent [Abstract]
Property, plant and equipment, net	0		0		816
Goodwill and intangibles	0		0		3,936
Other non-current assets	0		0		230
Assets of discontinued operations - non-current	0		0		4,983
Disposal Group, Including Discontinued Operation, Liabilities, Current [Abstract]
Short term debt	366		366		273
Trade accounts payables	4,608		4,608		4,313
Accrued expenses and other liabilities	759		759		746
Income taxes	11		11		14
Deferred income taxes	139		139		0
Other liabilities	308		308		0
Liabilities of discontinued operations - current	6,191		6,191		5,347
Disposal Group, Including Discontinued Operation, Liabilities, Noncurrent [Abstract]
Deferred income taxes	0		0		131
Other non-current liabilities	0		0		280
Liabilities of discontinued operations - non-current	0		0		$ 412
Discontinued Operations, Held-for-sale | Alliance Healthcare | Continuing Operations
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Sales	471	448	1,385	1,370
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Sales	$ 471	$ 448	$ 1,385	$ 1,370