Segment reporting (Details) $ in Millions	3 Months Ended
Nov. 30, 2020 USD ($) segment	Nov. 30, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	3
Sales	$ 36,307	$ 34,339
Adjusted operating income	1,318	1,463
Adjustments to equity earnings (loss) in AmerisourceBergen	(1,481)	(80)
Acquisition-related amortization	(116)	(118)
Transformational cost management	(104)	(86)
LIFO provision	(33)	(33)
Acquisition-related costs	(23)	(124)
Store optimization	0	(9)
Operating income (loss)	(440)	1,013
Reportable Segments \| Retail Pharmacy USA
Segment Reporting Information [Line Items]
Sales	27,163	26,133
Adjusted operating income	989	1,155
Reportable Segments \| Retail Pharmacy International
Segment Reporting Information [Line Items]
Sales	2,574	2,745
Adjusted operating income	84	79
Reportable Segments \| Pharmaceutical Wholesale
Segment Reporting Information [Line Items]
Sales	7,125	6,007
Adjusted operating income	244	229
Eliminations
Segment Reporting Information [Line Items]
Sales	(555)	(545)
Adjusted operating income	$ 1	$ 0

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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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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