Income tax - Schedule of Prior Period Income Tax Provision (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2023
Current:
International	$ 23
United Kingdom	458	$ 3	$ 0
Total current	606	604	679
Deferred:
International	4
United Kingdom	(36)	155	17
Total deferred	(39)	125	(104)
Provision for income taxes	$ 567	729	575
Foreign, United States
Current:
International		552	624
Deferred:
International		(32)	(120)
Foreign, Excluding United States
Current:
International		49	55
Deferred:
International		$ 2	$ (1)

Amount of current federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, current national tax expense (benefit) for non-US (United States of America) jurisdiction.

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