Income tax - Schedule of Income Tax by Geographical Area (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2023
Investments, Owned, Federal Income Tax Note [Line Items]
Income before income taxes	$ 2,423	$ 2,464	$ 2,464
UNITED STATES
Investments, Owned, Federal Income Tax Note [Line Items]
Foreign	2,263
Foreign, United States
Investments, Owned, Federal Income Tax Note [Line Items]
Foreign		2,022	2,011
Foreign, Excluding United States
Investments, Owned, Federal Income Tax Note [Line Items]
Foreign	$ 160	$ 442	$ 453