Segment reporting (Details) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2024 USD ($)	May 31, 2023 USD ($)	May 31, 2024 USD ($) segment	May 31, 2023 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment			3
Segment Reporting Information [Line Items]
Sales	$ 36,351	$ 35,415	$ 110,111	$ 103,659
Adjusted operating income (Non-GAAP measure)	613	959	2,200	3,188
Acquisition-related amortization	(266)	(274)	(811)	(851)
Transformational cost management	(95)	(414)	(401)	(697)
Acquisition-related costs	(68)	(70)	(480)	(257)
Adjustments to equity earnings in Cencora	(57)	(61)	(129)	(178)
Certain legal and regulatory accruals and settlements	(52)	(268)	(376)	(7,249)
LIFO provision	36	(51)	(11)	(89)
Impairment of goodwill, intangibles and long-lived assets	0	(299)	(13,091)	(299)
Operating income (loss)	111	(477)	(13,099)	(6,431)
Reportable Segments | U.S. Retail Pharmacy
Segment Reporting Information [Line Items]
Sales	28,503	27,866	86,308	82,648
Adjusted operating income (Non-GAAP measure)	501	962	1,947	3,134
Reportable Segments | International
Segment Reporting Information [Line Items]
Sales	5,727	5,573	17,581	16,414
Adjusted operating income (Non-GAAP measure)	175	208	562	676
Reportable Segments | U.S. Healthcare
Segment Reporting Information [Line Items]
Sales	2,125	1,975	6,232	4,597
Adjusted operating income (Non-GAAP measure)	(22)	(172)	(151)	(483)
Corporate and Other
Segment Reporting Information [Line Items]
Sales	(3)	0	(9)	0
Adjusted operating income (Non-GAAP measure)	$ (42)	$ (39)	$ (158)	$ (139)