Retirement and Post-Retirement Benefit Plans (Details 4) - USD ($) $ in Millions		12 Months Ended
		Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Change in benefit obligation:
Settlement	[1]	$ 64	$ 0	$ 7
Defined Benefit Plans | U.S. Plans
Change in benefit obligation:
Projected benefit obligation—beginning of year		7
Projected benefit obligation—end of year(3)		5	7
Defined Benefit Plans | U.S. Plans | Discontinued Operations, Disposed of by Means Other than Sale [Member] | Everett Transaction
Change in fair value of plan assets:
Transfer to Everett/Seattle plans		(702)
Change in benefit obligation:
Decrease from transfer		503
Defined Benefit Plans | U.S. Plans | Discontinued Operations, Disposed of by Means Other than Sale [Member] | Seattle Transaction
Change in fair value of plan assets:
Transfer to Everett/Seattle plans		(97)
Change in benefit obligation:
Decrease from transfer		165
Defined Benefit Plans | Non-U.S. Plans
Change in fair value of plan assets:
Fair value—beginning of year		11,989	11,684
Transfer to Everett/Seattle plans		(799)	0
Addition/deletion of plans(2)		5	141
Actual return on plan assets		941	1,212
Employer contributions		266	242
Participant contributions		17	40
Benefits paid		(408)	(344)
Settlement		(60)	(16)
Currency impact		659	(970)
Fair value—end of year(3)		12,610	11,989	11,684
Change in benefit obligation:
Projected benefit obligation—beginning of year		13,555	12,483
Transfer from Parent		(668)	0
Addition/deletion of plans(2)		19	25
Service cost		139	199	48
Interest cost		213	317	85
Participant contributions		17	40
Actuarial (gain) loss		(445)	1,832
Benefits paid		(408)	(344)
Plan amendments		(1)	1
Curtailment		(1)	0
Settlement		(60)	(16)
Special termination benefits		5	5
Currency impact		704	(987)
Projected benefit obligation—end of year(3)		13,069	13,555	12,483
Funded status at end of year		(459)	(1,566)
Accumulated benefit obligation		$ 12,832	$ 13,241
Weighted average assumptions used to calculate the projected benefit obligations for Direct plans:
Discount rate		2.00%	1.70%
Expected increase in compensation levels		2.30%	2.30%
Net amounts recognized for the Direct plans in Combined and Consolidated Balance Sheets:
Non-current assets		$ 830	$ 366
Current liabilities		(39)	(20)
Non-current liabilities		(1,250)	(1,912)
Funded status at end of year		(459)	(1,566)
Pretax net actuarial loss (gain) and prior service benefit recognized in accumulated other comprehensive loss for and prior service benefit recognized in Accumulated other comprehensive loss for the Direct defined benefit plans:
Net actuarial loss (gain)		2,777
Prior service benefit		(103)
Total recognized in accumulated other comprehensive loss		2,674
Net actuarial loss and prior service benefit for Direct plans that are expected to be amortized from Accumulated other comprehensive loss and recognized as components of net periodic benefit cost (credit):
Net actuarial loss (gain)		206
Prior service benefit		(17)
Total expected to be recognized in net periodic benefit cost (credit)		189
Direct defined benefit plans with projected benefit obligations exceeding the fair value of plan assets:
Aggregate fair value of plan assets		2,596	6,193
Aggregate projected benefit obligation		3,884	8,125
Direct defined benefit plans with accumulated benefit obligations exceeding the fair value of plan assets:
Aggregate fair value of plan assets		1,272	5,856
Aggregate accumulated benefit obligation		2,476	7,518
Defined Benefit Plans | Non-U.S. Plans | Discontinued Operations, Disposed of by Means Other than Sale [Member] | Everett Transaction
Change in fair value of plan assets:
Employer contributions		1,900
Post-Retirement Benefit Plans
Change in fair value of plan assets:
Fair value—beginning of year		47	40
Transfer to Everett/Seattle plans		0	0
Addition/deletion of plans(2)		0	0
Actual return on plan assets		1	1
Employer contributions		4	3
Participant contributions		4	6
Benefits paid		(6)	(3)
Settlement		0	0
Currency impact		0	0
Fair value—end of year(3)		50	47	40
Change in benefit obligation:
Projected benefit obligation—beginning of year		158	139
Transfer from Parent		0	0
Addition/deletion of plans(2)		0	0
Service cost		3	3	0
Interest cost		6	6	1
Participant contributions		4	6
Actuarial (gain) loss		4	6
Benefits paid		(6)	(3)
Plan amendments		0	0
Curtailment		0	0
Settlement		0	0
Special termination benefits		0	0
Currency impact		1	1
Projected benefit obligation—end of year(3)		170	158	$ 139
Funded status at end of year		(120)	(111)
Accumulated benefit obligation		$ 0	$ 0
Weighted average assumptions used to calculate the projected benefit obligations for Direct plans:
Discount rate		4.50%	4.20%
Expected increase in compensation levels		0.00%	0.00%
Net amounts recognized for the Direct plans in Combined and Consolidated Balance Sheets:
Non-current assets		$ 0	$ 0
Current liabilities		(4)	(3)
Non-current liabilities		(116)	(108)
Funded status at end of year		(120)	$ (111)
Pretax net actuarial loss (gain) and prior service benefit recognized in accumulated other comprehensive loss for and prior service benefit recognized in Accumulated other comprehensive loss for the Direct defined benefit plans:
Net actuarial loss (gain)		(2)
Prior service benefit		0
Total recognized in accumulated other comprehensive loss		(2)
Net actuarial loss and prior service benefit for Direct plans that are expected to be amortized from Accumulated other comprehensive loss and recognized as components of net periodic benefit cost (credit):
Net actuarial loss (gain)		(3)
Prior service benefit		0
Total expected to be recognized in net periodic benefit cost (credit)		$ (3)

[1] In fiscal 2017, represents adjustments to the net periodic pension cost resulting from remeasurements of Hewlett Packard Enterprise pension plans due to plan separations in connection with the separation and merger of Seattle SpinCo, Inc. with Micro Focus and Everett SpinCo, Inc. with Computer Sciences Corporation. In fiscal 2015, Defined benefit plan settlement charges and remeasurement (benefit), was related to U.S. defined benefit plan settlement expense and net periodic benefit cost resulting from former Parent's voluntary lump sum program announced in January 2015.