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, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Segment Information
Net revenue	$ 13,060	$ 11,892	$ 38,129	$ 35,726
Total segment earnings from operations	955	1,117	2,629	2,886
Stock-based compensation expense	(46)	(39)	(169)	(140)
Restructuring and other charges	(46)	(36)	(249)	(156)
Acquisition-related charges	(40)	0	(76)	0
Amortization of intangible assets	0	(2)	(1)	(16)
Defined benefit plan settlement charges	(1)	0	(4)	0
Interest and other, net	(56)	(36)	(201)	(135)
Earnings from continuing operations before taxes	899	1,081	2,428	2,751
Operating segments
Segment Information
Net revenue	13,104	11,935	38,221	35,677
Total segment earnings from operations	1,106	1,201	3,155	3,229
Net revenue eliminations and other
Segment Information
Net revenue	(44)	(43)	(92)	49
Corporate and unallocated costs and eliminations
Segment Information
Corporate and unallocated costs and eliminations	(18)	(7)	(27)	(31)
Segment reconciling items
Segment Information
Stock-based compensation expense	(46)	(39)	(169)	(140)
Restructuring and other charges	(46)	(36)	(249)	(156)
Acquisition-related charges	(40)	0	(76)	0
Amortization of intangible assets	0	(2)	(1)	(16)
Defined benefit plan settlement charges	(1)	0	(4)	0
Interest and other, net	$ (56)	$ (36)	$ (201)	$ (135)

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Amount of reconciling item for corporate and unallocated costs, gains and eliminations.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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