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		6 Months Ended
	Feb. 29, 2024	Feb. 28, 2023	Feb. 29, 2024	Feb. 28, 2023
Total return swaps | Selling, general and administrative expenses
Derivatives, Fair Value [Line Items]
Loss on variable prepaid forward contracts	$ 18	$ (3)	$ 17	$ 0
Foreign currency forwards | Other income, net
Derivatives, Fair Value [Line Items]
Loss on variable prepaid forward contracts	(26)	(73)	33	(92)
Variable Prepaid Forward | Other income, net
Derivatives, Fair Value [Line Items]
Loss on variable prepaid forward contracts	$ (522)	$ 0	$ (888)	$ 0