Segment Information - Schedule of Reconciliation of Segment Operating Results to HP Consolidated Results (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Segment Information
Net revenue	$ 12,469	$ 14,036	$ 27,087	$ 28,746
Total segment earnings from operations	826	928	1,691	1,854
Restructuring and other charges	(81)	(69)	(372)	(124)
Acquisition-related charges	(3)	(11)	(3)	(21)
Amortization of intangible assets	(29)	(29)	(55)	(58)
Interest and other, net	0	(45)	13	(71)
Total earnings before taxes	826	883	1,704	1,783
Operating segments
Segment Information
Net revenue	12,471	14,037	27,088	28,751
Total segment earnings from operations	1,086	1,200	2,489	2,407
Other
Segment Information
Net revenue	(2)	(1)	(1)	(5)
Corporate and unallocated costs and other	(84)	(97)	(196)	(177)
Stock-based compensation expense	(63)	(66)	(172)	(173)
Restructuring and other charges	(81)	(69)	(372)	(124)
Acquisition-related charges	(3)	(11)	(3)	(21)
Amortization of intangible assets	(29)	(29)	(55)	(58)
Interest and other, net	0	(45)	13	(71)
Personal Systems \| Operating segments
Segment Information
Net revenue	8,313	8,921	18,205	18,578
Total segment earnings from operations	552	385	1,214	795
Printing \| Operating segments
Segment Information
Net revenue	4,158	5,116	8,882	10,172
Total segment earnings from operations	548	839	1,302	1,660
Corporate Investments \| Operating segments
Segment Information
Net revenue	0	0	1	1
Total segment earnings from operations	(14)	(24)	(27)	(48)
Notebooks \| Personal Systems \| Operating segments
Segment Information
Net revenue	5,083	5,099	11,057	11,018
Desktops \| Personal Systems \| Operating segments
Segment Information
Net revenue	2,409	2,940	5,332	5,797
Workstations \| Personal Systems \| Operating segments
Segment Information
Net revenue	439	569	1,033	1,131
Other \| Personal Systems \| Operating segments
Segment Information
Net revenue	382	313	783	632
Supplies \| Printing \| Operating segments
Segment Information
Net revenue	2,841	3,331	5,882	6,598
Commercial Hardware \| Printing \| Operating segments
Segment Information
Net revenue	808	1,179	1,884	2,269
Consumer Hardware \| Printing \| Operating segments
Segment Information
Net revenue	$ 509	$ 606	$ 1,116	$ 1,305

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