Share-based compensation - Schedule of Time Vested, Performance Vested and Long-Term Incentive Awards (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2023
Share-Based Payment Arrangement [Abstract]
Fair value of awards vested	$ 84	$ 79	$ 67
Weighted-average grant date fair value per share granted (in usd per share)	$ 186.18	$ 158.32	$ 99.95

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration