Summary of Significant Accounting Policies - Product Warranty Liability (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016	Oct. 31, 2016	Oct. 31, 2015
Product Liability Contingency [Line Items]
Document Type			10-Q
Product Warranty Accrual	$ 659	$ 868	$ 659	$ 868	$ 818	$ 994
Product Warranty Accrual, Warranties Issued			137	141
Product Warranty Accrual, Currency Translation, Increase (Decrease)			0	2
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Adjustments to pre-existing warranties(A)(B)			(4)	70
Extended Warranty Program:
Product Warranty Accrual, Payments			(292)	(339)
Product Warranty Accrual, Current	340	423	340	423
Product Warranty Accrual, Noncurrent	319	445	319	445
Extended Warranty Programs [Member]
Extended Warranty Program:
Deferred Revenue, Revenue Recognized	28	$ 37	109	$ 113
Deferred Revenue	$ 280		$ 280		$ 325