Equity method investments - Schedule of Equity Method Investments (Details) - USD ($) $ in Millions	Nov. 30, 2022	Aug. 31, 2022
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 4,426	$ 5,495
AmerisourceBergen
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 2,877	$ 3,916
Ownership percentage	19.60%	25.40%
Others
Schedule of Equity Method Investments [Line Items]
Carrying value of equity method investments	$ 1,548	$ 1,579
Others | Minimum
Schedule of Equity Method Investments [Line Items]
Ownership percentage	4.00%	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	$ 4,426	$ 5,495