Accumulated other comprehensive loss - Schedule of Change in AOCI (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Apr. 30, 2025	Jan. 31, 2025	Oct. 31, 2024	Apr. 30, 2024	Jan. 31, 2024	Oct. 31, 2023	Apr. 30, 2025	Apr. 30, 2024
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ 5,616				$ 5,616
Other comprehensive loss before reclassifications	$ 44	$ (33)	(5)	$ (20)	$ 23	$ (37)
Amounts reclassified from accumulated other comprehensive loss	4	2	3	3	2	3
Total other comprehensive income (loss), net of tax	48	(31)	(2)	(17)	25	(34)	15	$ (26)
Ending balance	5,531			5,522			5,531	5,522
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(964)	(933)	(931)	(897)	(922)	(888)	(931)	(888)
Total other comprehensive income (loss), net of tax	48			(17)			15	(26)
Ending balance	(916)	(964)	(933)	(914)	(897)	(922)	(916)	(914)
Foreign currency translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(500)	(468)	(461)	(443)	(464)	(429)	(461)	(429)
Other comprehensive loss before reclassifications	40	(32)	(7)	(19)	21	(35)
Amounts reclassified from accumulated other comprehensive loss	0	0	0	0	0	0
Total other comprehensive income (loss), net of tax	40	(32)	(7)	(19)	21	(35)
Ending balance	(460)	(500)	(468)	(462)	(443)	(464)	(460)	(462)
Pensions
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(464)	(465)	(470)	(454)	(458)	(459)	(470)	(459)
Other comprehensive loss before reclassifications	4	(1)	2	(1)	2	(2)
Amounts reclassified from accumulated other comprehensive loss	4	2	3	3	2	3
Total other comprehensive income (loss), net of tax	8	1	5	2	4	1
Ending balance	$ (456)	$ (464)	$ (465)	$ (452)	$ (454)	$ (458)	$ (456)	$ (452)