Segment Information - Segment Operating Results from Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2025	Jul. 31, 2024
Segment Reporting Information [Line Items]
Net revenue	$ 9,136	$ 7,710	$ 24,617	$ 21,669
Segment earnings (loss) from operations	247	547	(429)	1,497
Intersegment net revenue
Segment Reporting Information [Line Items]
Net revenue	(98)	(132)	(251)	(413)
Operating Segment
Segment Reporting Information [Line Items]
Net revenue	9,234	7,842	24,868	22,082
Segment earnings (loss) from operations	838	856	2,351	2,448
Server
Segment Reporting Information [Line Items]
Net revenue	4,903	4,192	13,202	11,199
Server \| Intersegment net revenue
Segment Reporting Information [Line Items]
Net revenue	(37)	(63)	(86)	(224)
Server \| Operating Segment
Segment Reporting Information [Line Items]
Net revenue	4,940	4,255	13,288	11,423
Segment earnings (loss) from operations	317	461	906	1,263
Hybrid Cloud
Segment Reporting Information [Line Items]
Net revenue	1,422	1,269	4,182	3,718
Hybrid Cloud \| Intersegment net revenue
Segment Reporting Information [Line Items]
Net revenue	(62)	(56)	(160)	(162)
Hybrid Cloud \| Operating Segment
Segment Reporting Information [Line Items]
Net revenue	1,484	1,325	4,342	3,880
Segment earnings (loss) from operations	87	69	264	133
Networking
Segment Reporting Information [Line Items]
Net revenue	1,732	1,110	4,035	3,384
Networking \| Intersegment net revenue
Segment Reporting Information [Line Items]
Net revenue	2	(11)	(3)	(24)
Networking \| Operating Segment
Segment Reporting Information [Line Items]
Net revenue	1,730	1,121	4,038	3,408
Segment earnings (loss) from operations	360	251	948	841
Financial Services
Segment Reporting Information [Line Items]
Net revenue	887	877	2,616	2,616
Financial Services \| Intersegment net revenue
Segment Reporting Information [Line Items]
Net revenue	1	(2)	1	(3)
Financial Services \| Operating Segment
Segment Reporting Information [Line Items]
Net revenue	886	879	2,615	2,619
Segment earnings (loss) from operations	88	79	259	234
Corporate Investments and Other
Segment Reporting Information [Line Items]
Net revenue	192	262	582	752
Corporate Investments and Other \| Intersegment net revenue
Segment Reporting Information [Line Items]
Net revenue	(2)	0	(3)	0
Corporate Investments and Other \| Operating Segment
Segment Reporting Information [Line Items]
Net revenue	194	262	585	752
Segment earnings (loss) from operations	$ (14)	$ (4)	$ (26)	$ (23)