Segment reporting (Details) $ in Millions	3 Months Ended	9 Months Ended
May 31, 2025 USD ($)	May 31, 2024 USD ($)	May 31, 2025 USD ($) segment	May 31, 2024 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment			3
Segment Reporting Information [Line Items]
Sales	$ 38,986	$ 36,351	$ 117,034	$ 110,111
Adjusted operating income (Non-GAAP measure)	558	613	1,936	2,200
Acquisition-related amortization	(226)	(266)	(746)	(811)
Impairment of goodwill, intangibles and long-lived assets	(89)	0	(5,432)	(13,091)
Footprint optimization	(73)	0	(473)	0
Acquisition and disposition-related costs	(62)	(68)	(260)	(480)
Certain legal and regulatory accruals and settlements	(49)	(52)	(656)	(376)
Adjustments to equity earnings in Cencora	(13)	(57)	(122)	(129)
Transformational cost management	(3)	(95)	9	(401)
LIFO provision	10	36	(14)	(11)
Operating income (loss)	53	111	(5,759)	(13,099)
Reportable Segments \| U.S. Retail Pharmacy
Segment Reporting Information [Line Items]
Sales	30,715	28,503	91,961	86,308
Adjusted operating income (Non-GAAP measure)	350	501	1,278	1,947
Reportable Segments \| International
Segment Reporting Information [Line Items]
Sales	6,172	5,727	18,657	17,581
Adjusted operating income (Non-GAAP measure)	214	175	615	562
Reportable Segments \| U.S. Healthcare
Segment Reporting Information [Line Items]
Sales	2,102	2,125	6,427	6,232
Adjusted operating income (Non-GAAP measure)	54	(22)	196	(151)
Reportable Segments \| Pharmacy \| U.S. Retail Pharmacy
Segment Reporting Information [Line Items]
Sales	24,381	21,812	72,524	65,704
Reportable Segments \| Pharmacy \| International
Segment Reporting Information [Line Items]
Sales	913	874	2,662	2,698
Reportable Segments \| Retail \| U.S. Retail Pharmacy
Segment Reporting Information [Line Items]
Sales	6,334	6,691	19,437	20,604
Reportable Segments \| Retail \| International
Segment Reporting Information [Line Items]
Sales	1,976	1,839	6,274	5,928
Reportable Segments \| Wholesale \| International
Segment Reporting Information [Line Items]
Sales	3,283	3,014	9,721	8,955
Corporate and Other
Segment Reporting Information [Line Items]
Sales	(4)	(3)	(12)	(9)
Adjusted operating income (Non-GAAP measure)	$ (60)	$ (42)	$ (152)	$ (158)

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