Shareholders’ equity - Narrative (Details) $ in Millions	12 Months Ended
	Jul. 31, 2024 USD ($) trust shares	Aug. 01, 2024 shares	Jul. 31, 2023 shares
Class of Stock [Line Items]
Number of employee benefit trusts | trust	2
Proceeds from shares sold in period | $	$ 4
Authorized stock to repurchased | $	4,000
Stock repurchased | $	$ 3,100
Ordinary shares, shares issued (in shares) | shares	232,171,182		232,171,182
Subsequent Event
Class of Stock [Line Items]
Ordinary shares, shares issued (in shares) | shares		201,343,253
Ordinary shares, shares outstanding (in shares) | shares		201,343,253