Segment reporting - results of operations of reportable segments (Details) - USD ($) $ in Millions	12 Months Ended
Aug. 31, 2024	Aug. 31, 2023	Aug. 31, 2022
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	$ 147,658	$ 139,081	$ 132,703
Adjusted operating income:	2,624	3,871	5,133
Depreciation and amortization	2,459	2,257	1,990
Capital expenditures:	1,381	2,117	1,734
Impairment of goodwill, intangibles and long-lived assets	(13,422)	(299)	(783)
Acquisition-related amortization	(1,075)	(1,126)	(855)
Transformational cost management	(891)	(1,181)	(763)
Acquisition-related costs	(542)	(323)	(223)
Certain legal and regulatory accruals and settlements	(561)	(7,466)	(768)
Adjustments to equity earnings in Cencora	(162)	(211)	(218)
LIFO provision	(47)	(187)	(135)
Store damage and inventory loss insurance recovery	0	40	0
Operating (loss) income	(14,076)	(6,882)	1,387
Reportable Segments \| U.S. Retail Pharmacy
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	115,778	110,314	109,078
Adjusted operating income:	2,167	3,689	5,029
Depreciation and amortization	1,422	1,362	1,415
Capital expenditures:	(1,041)	1,421	(1,207)
Reportable Segments \| U.S. Retail Pharmacy \| Pharmacy
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	88,867	82,118	80,434
Reportable Segments \| U.S. Retail Pharmacy \| Retail
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	26,911	28,195	28,643
Reportable Segments \| International
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	23,552	22,198	21,830
Adjusted operating income:	793	935	726
Depreciation and amortization	370	328	355
Capital expenditures:	(247)	308	(295)
Reportable Segments \| International \| Pharmacy
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	3,598	3,664	3,727
Reportable Segments \| International \| Retail
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	7,887	7,324	6,924
Reportable Segments \| International \| Wholesale
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	12,067	11,211	11,178
Reportable Segments \| U.S. Healthcare
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	8,345	6,570	1,795
Adjusted operating income:	(134)	(566)	(370)
Depreciation and amortization	651	560	211
Capital expenditures:	91	375	218
Corporate and Other
Segment Reporting Information, Operating Income (Loss) [Abstract]
Sales	(16)	0	0
Adjusted operating income:	(202)	(187)	(251)
Depreciation and amortization	16	8	9
Capital expenditures:	$ 2	$ 13	$ 15

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

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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The total amount of adjusted operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

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This item represents the adjustments to equity earnings proportionate share for the period of the net income (loss) of AmerisourceBergen (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied.

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Depreciation, Depletion and Amortization, Excluding Discontinued Operations

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Payments To Acquire Property, Plant, And Equipment, Excluding Discontinued Operations

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Restructuring and Related Costs, Store Damage And Inventory Losses

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Transformational Cost Management

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