Financial instruments - Summary of Derivative Income and Expenses Due to Fair Value Changes (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions	3 Months Ended
Nov. 30, 2023	Nov. 30, 2022
Total return swaps \| Selling, general and administrative expenses
Derivatives, Fair Value [Line Items]
Loss on variable prepaid forward contracts	$ (1)	$ 4
Foreign currency forwards \| Other income, net
Derivatives, Fair Value [Line Items]
Loss on variable prepaid forward contracts	59	(18)
Variable Prepaid Forward \| Other income, net
Derivatives, Fair Value [Line Items]
Loss on variable prepaid forward contracts	$ (366)	$ 0

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 25
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480238/815-25-50-1

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration