Segment reporting (Details) $ in Millions	3 Months Ended	6 Months Ended
Feb. 29, 2024 USD ($)	Feb. 28, 2023 USD ($)	Feb. 29, 2024 USD ($) segment	Feb. 28, 2023 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment			3
Segment Reporting Information [Line Items]
Sales	$ 37,052	$ 34,862	$ 73,760	$ 68,244
Adjusted operating income (Non-GAAP measure)	900	1,215	1,588	2,229
Impairment of goodwill, intangibles and long-lived assets	(13,090)	0	(13,090)	0
Acquisition-related costs	(249)	(148)	(412)	(187)
Acquisition-related amortization	(270)	(247)	(545)	(577)
Certain legal and regulatory accruals and settlements	(242)	(427)	(324)	(6,981)
Transformational cost management	(197)	(145)	(306)	(283)
Adjustments to equity earnings in Cencora	(22)	(31)	(72)	(117)
LIFO provision	0	(20)	(48)	(38)
Operating (loss) income	(13,171)	197	(13,209)	(5,954)
Reportable Segments \| U.S. Retail Pharmacy
Segment Reporting Information [Line Items]
Sales	28,861	27,577	57,805	54,781
Adjusted operating income (Non-GAAP measure)	752	1,067	1,446	2,172
Reportable Segments \| International
Segment Reporting Information [Line Items]
Sales	6,022	5,651	11,854	10,840
Adjusted operating income (Non-GAAP measure)	245	352	387	468
Reportable Segments \| U.S. Healthcare
Segment Reporting Information [Line Items]
Sales	2,176	1,634	4,107	2,622
Adjusted operating income (Non-GAAP measure)	(34)	(159)	(129)	(311)
Corporate and Other
Segment Reporting Information [Line Items]
Sales	(6)	0	(6)	0
Adjusted operating income (Non-GAAP measure)	$ (63)	$ (44)	$ (117)	$ (100)

The amount of expense recognized in the current period that reflects the allocation of capitalized costs associated with acquisition of business. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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