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Financial instruments - Summary of Derivative Income and Expenses Due to Fair Value Changes (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	May 31, 2025	Feb. 28, 2025	May 31, 2024	May 31, 2025	May 31, 2024
Realized Gain (Loss) \| Derivative Financial Instruments, Liabilities
Derivatives, Fair Value [Line Items]
Unrealized and realized gains (losses) recorded in Other income (expense), net	$ 378	$ 955	$ 0	$ 1,333	$ 0
Derivatives not designated as hedges: \| Total return swaps \| Selling, general and administrative expenses
Derivatives, Fair Value [Line Items]
(Gain) loss on variable prepaid forward contracts	(2)		2	3	19
Derivatives not designated as hedges: \| Foreign currency forwards \| Other income (expense), net
Derivatives, Fair Value [Line Items]
(Gain) loss on variable prepaid forward contracts	(170)		(14)	(87)	19
Derivatives not designated as hedges: \| Variable prepaid forward contracts \| Other income (expense), net
Derivatives, Fair Value [Line Items]
(Gain) loss on variable prepaid forward contracts	$ (11)		$ 155	$ 766	$ (733)