Equity method investments - Schedule of Equity Method Investments (Details) - USD ($) $ in Millions	Feb. 29, 2024	Aug. 31, 2023
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 3,256	$ 3,497
Cencora
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 2,183	$ 2,534
Ownership percentage	13.50%	15.90%
Others
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 1,073	$ 963
Others | Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage	8.00%	8.00%
Others | Maximum
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%	50.00%
Total
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 3,256	$ 3,497