Acquisitions and other investments - Schedule of Pro Forma and Actual Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
May 31, 2023	May 31, 2022	May 31, 2023	May 31, 2022
Summit Health-CityMD
Business Acquisition [Line Items]
Sales, pro forma	$ 35,415	$ 33,303	$ 104,630	$ 102,228
Sales, actual	$ 730		$ 1,193
VillageMD, Shields And CareCentrix
Business Acquisition [Line Items]
Sales, pro forma		32,910		101,537
Sales, actual		$ 596		$ 1,173

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
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-Publisher FASB
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(2)
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