Segment reporting (Details) $ in Millions	3 Months Ended
Nov. 30, 2023 USD ($) segment	Nov. 30, 2022 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment	3
Segment Reporting Information [Line Items]
Sales	$ 36,707	$ 33,382
Adjusted operating income (Non-GAAP measure)	687	1,014
Acquisition-related amortization	(275)	(330)
Acquisition-related costs	(163)	(39)
Transformational cost management	(109)	(138)
Certain legal and regulatory accruals and settlements	(82)	(6,554)
Adjustments to equity earnings in Cencora	(50)	(86)
LIFO provision	(48)	(18)
Operating loss	(39)	(6,151)
Reportable Segments \| U.S. Retail Pharmacy
Segment Reporting Information [Line Items]
Sales	28,944	27,204
Adjusted operating income (Non-GAAP measure)	694	1,105
Reportable Segments \| International
Segment Reporting Information [Line Items]
Sales	5,832	5,189
Adjusted operating income (Non-GAAP measure)	142	116
Reportable Segments \| U.S. Healthcare
Segment Reporting Information [Line Items]
Sales	1,931	989
Adjusted operating income (Non-GAAP measure)	(96)	(152)
Corporate and Other
Segment Reporting Information [Line Items]
Adjusted operating income (Non-GAAP measure)	$ (53)	$ (56)

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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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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