Retirement and Post-Retirement Benefit Plan - Schedule of Funded Status of Defined Benefit and Post-Retirement Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Post-Retirement Benefit Plans
Change in fair value of plan assets:
Fair value of assets — beginning of year	$ 390	$ 434
Actual return on plan assets	26	11
Employer contributions	9	18
Participant contributions	53	48
Benefits paid	(127)	(121)
Settlement	0	0
Currency impact	0	0
Transfers to Hewlett Packard Enterprise	0	0
Fair value of assets — end of year	351	390	$ 434
Change in benefits obligation
Projected benefit obligation — beginning of year	535	597
Acquisition/addition of plans	0	0
Service cost	1	1	5
Interest cost	18	20	28
Participant contributions	53	48
Actuarial loss (gain)	(17)	16
Benefits paid	(127)	(121)
Plan amendments	0	(30)
Curtailment	0	0
Settlement	0	0
Special termination benefits	0	4
Currency impact	0	0
Transfers to Hewlett Packard Enterprise	0	0
Projected benefit obligation — end of year	463	535	597
Funded status at end of year	(112)	(145)
Accumulated benefit obligation	0	0
United States \| Defined Benefit Plans
Change in fair value of plan assets:
Fair value of assets — beginning of year	10,176	11,077
Actual return on plan assets	1,223	736
Employer contributions	33	32
Participant contributions	0	0
Benefits paid	(583)	(339)
Settlement	(11)	(1,330)
Currency impact	0	0
Transfers to Hewlett Packard Enterprise	0	0
Fair value of assets — end of year	10,838	10,176	11,077
Change in benefits obligation
Projected benefit obligation — beginning of year	12,144	12,709
Acquisition/addition of plans	0	0
Service cost	0	0	1
Interest cost	469	543	556
Participant contributions	0	0
Actuarial loss (gain)	247	561
Benefits paid	(583)	(339)
Plan amendments	0	0
Curtailment	0	0
Settlement	(11)	(1,330)
Special termination benefits	0	0
Currency impact	0	0
Transfers to Hewlett Packard Enterprise	0	0
Projected benefit obligation — end of year	12,266	12,144	12,709
Funded status at end of year	(1,428)	(1,968)
Accumulated benefit obligation	12,266	12,144
Non-U.S. \| Defined Benefit Plans
Change in fair value of plan assets:
Fair value of assets — beginning of year	692	853
Actual return on plan assets	86	(14)
Employer contributions	27	20
Participant contributions	10	10
Benefits paid	(14)	(15)
Settlement	(6)	(9)
Currency impact	20	4
Transfers to Hewlett Packard Enterprise	0	(157)
Fair value of assets — end of year	815	692	853
Change in benefits obligation
Projected benefit obligation — beginning of year	1,120	1,082
Acquisition/addition of plans	0	(2)
Service cost	48	47	208
Interest cost	18	20	289
Participant contributions	10	10
Actuarial loss (gain)	(77)	120
Benefits paid	(14)	(15)
Plan amendments	(3)	0
Curtailment	0	(1)
Settlement	(6)	(9)
Special termination benefits	0	0
Currency impact	36	(4)
Transfers to Hewlett Packard Enterprise	0	(128)
Projected benefit obligation — end of year	1,132	1,120	$ 1,082
Funded status at end of year	(317)	(428)
Accumulated benefit obligation	$ 1,014	$ 1,013

Defined Benefit Plan, Change in Benefit Obligation, Benefits Paid

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Represents the defined benefit fund obligation transferred in spin-off transaction.

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Represents the transfers in spin-off transaction of funds Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of contributions received by defined benefit plan from participant which increase benefit obligation.

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Amount of increase in benefit obligation of defined benefit plan from business combination.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Amount of (increase) decrease in benefit obligation of defined benefit plan from event reducing expected years of future service of present employees or eliminating accrual of benefits for some or all future services of present employees.

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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Amount of foreign currency translation gain (loss) which (increases) decreases benefit obligation of defined benefit plan.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Amount of contributions received by defined benefit plan from participant which increases plan assets.

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Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

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Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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Amount of increase in benefit obligation for benefits provided to employees payable from defined benefit plan or payable upon retirement.

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