Financial instruments - warrants (Details) - Derivatives not designated as hedges: - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2023	Aug. 31, 2022	Aug. 31, 2021
Foreign currency forwards | Selling, general and administrative expense
Warrants [Abstract]
Gains (losses) due to changes in fair value of derivative instruments	$ 0	$ 0	$ (75)
Foreign currency forwards | Other income (expense)
Warrants [Abstract]
Gains (losses) due to changes in fair value of derivative instruments	(273)	523	(8)
Total return swaps | Selling, general and administrative expense
Warrants [Abstract]
Gains (losses) due to changes in fair value of derivative instruments	12	(33)	58
Variable prepaid forward | Other income (expense)
Warrants [Abstract]
Gains (losses) due to changes in fair value of derivative instruments	$ 19	$ 0	$ 0