Segment Information - Schedule of Reconciliation of Segment Operating Results to HP Consolidated Results (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Segment Information
Net revenue	$ 14,294	$ 14,603	$ 41,381	$ 43,349
Total segment earnings from operations	779	1,079	2,470	2,933
Restructuring and other charges	(59)	(17)	(431)	(141)
Acquisition-related (charges) credits	(11)	9	(14)	(12)
Amortization of intangible assets	(29)	(29)	(84)	(87)
Interest and other, net	(28)	(831)	(15)	(902)
Total earnings before taxes	751	248	2,455	2,031
Operating segments
Segment Information
Net revenue	14,294	14,603	41,382	43,354
Total segment earnings from operations	1,035	1,289	3,524	3,696
Other
Segment Information
Net revenue	0	0	(1)	(5)
Corporate and unallocated costs and other	(108)	(113)	(304)	(290)
Stock-based compensation expense	(49)	(60)	(221)	(233)
Restructuring and other charges	(59)	(17)	(431)	(141)
Acquisition-related (charges) credits	(11)	9	(14)	(12)
Amortization of intangible assets	(29)	(29)	(84)	(87)
Interest and other, net	(28)	(831)	(15)	(902)
Personal Systems | Operating segments
Segment Information
Net revenue	10,360	9,690	28,565	28,268
Total segment earnings from operations	570	547	1,784	1,342
Printing | Operating segments
Segment Information
Net revenue	3,933	4,912	12,815	15,084
Total segment earnings from operations	480	765	1,782	2,425
Corporate Investments | Operating segments
Segment Information
Net revenue	1	1	2	2
Total segment earnings from operations	(15)	(23)	(42)	(71)
Notebooks | Personal Systems | Operating segments
Segment Information
Net revenue	7,304	5,630	18,361	16,648
Desktops | Personal Systems | Operating segments
Segment Information
Net revenue	2,221	3,111	7,553	8,908
Workstations | Personal Systems | Operating segments
Segment Information
Net revenue	428	609	1,461	1,740
Other | Personal Systems | Operating segments
Segment Information
Net revenue	407	340	1,190	972
Supplies | Printing | Operating segments
Segment Information
Net revenue	2,573	3,164	8,455	9,762
Commercial Hardware | Printing | Operating segments
Segment Information
Net revenue	732	1,160	2,616	3,429
Consumer Hardware | Printing | Operating segments
Segment Information
Net revenue	$ 628	$ 588	$ 1,744	$ 1,893