Discontinued operations - Schedules of Discontinued Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020	Aug. 31, 2020
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net earnings from discontinued operations	$ 107	$ 81	$ 194	$ 160
Disposal Group, Including Discontinued Operation, Assets, Current [Abstract]
Assets of discontinued operations - current	10,839		10,839		$ 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	6,228		6,228		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	5,243	4,948	10,570	9,835
Cost of sales	4,713	4,452	9,530	8,853
Gross profit	530	496	1,039	982
Selling, general and administrative expense	401	399	816	792
Operating income from discontinued operations	129	97	223	190
Other income (expense), net	(9)	(8)	(15)	(17)
Earnings before income tax – discontinued operations	120	89	208	173
Income tax provision	16	11	24	21
Post tax earnings (loss) from other equity method investments	3	3	10	7
Net earnings from discontinued operations	107	81	194	160
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Sales	5,243	4,948	10,570	9,835
Net Cash Provided by (Used in) Discontinued Operations [Abstract]
Cash used in operating activities - discontinued operations			(138)	(115)
Cash used for investing activities - discontinued operations			(31)	(27)
Disposal Group, Including Discontinued Operation, Assets, Current [Abstract]
Cash and cash equivalents	68		68		47
Accounts receivable, net	3,507		3,507		3,022
Inventories	1,771		1,771		1,534
Other current assets	339		339		376
Property, plant and equipment, net	894		894		0
Goodwill and intangibles	4,058		4,058		0
Other assets	202		202		0
Assets of discontinued operations - current	10,839		10,839		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	341		341		273
Trade accounts payables	4,704		4,704		4,313
Accrued expenses and other liabilities	723		723		746
Income taxes	10		10		14
Deferred income taxes	135		135		0
Other liabilities	315		315		0
Liabilities of discontinued operations - current	6,228		6,228		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	456	463	914	923
Disposal Group, Including Discontinued Operation, Additional Disclosures [Abstract]
Sales	$ 456	$ 463	$ 914	$ 923