Summary of Significant Accounting Policies - Product Warranty Liability (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			12 Months Ended
	Apr. 30, 2016	Oct. 31, 2015	Jan. 31, 2015	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2014
Product Liability Contingency [Line Items]
Document Type				10-K
Product Warranty Accrual		$ 994		$ 629	$ 818	$ 994	$ 1,197
Product Warranty Accrual, Warranties Issued				199	186	260
Product Warranty Accrual, Currency Translation, Increase (Decrease)				(1)	3	(9)
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Adjustments to pre-existing warranties(A)(B)				(1)	77	1
Extended Warranty Program:
Product Warranty Accrual, Payments				(386)	(442)	(455)
Product Warranty Accrual, Current		429		307	396	429
Product Warranty Accrual, Noncurrent		565		322	422	565
North America Truck [Member]
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Product Warranty Expense					34
Extended Warranty Programs [Member]
Extended Warranty Program:
Deferred Revenue, Revenue Recognized					150	154
Deferred Revenue		401		271	325	401
Product Warranty Accrual [Member]
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Adjustments to pre-existing warranties(A)(B)	$ 46	$ 40	$ (57)
Product Warranty Accrual, Preexisting Increase Decrease Per Share, Net of Tax	$ 0.56	$ 0.49	$ (0.70)
Discontinued Operations [Member] | Product Warranty Accrual [Member]
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Adjustments to pre-existing warranties(A)(B)					(1)	(3)
Field Campaign to address issues in products sold [Member] | North America Truck [Member]
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Product Warranty Expense				$ 21	17	$ 12
Pre-existing Warranty [Member] | North America Truck [Member]
Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:
Product Warranty Expense					$ 26
Minimum [Member]
Product Liability Contingency [Line Items]
Product Warranty Coverage Period				1 year
Maximum [Member]
Product Liability Contingency [Line Items]
Product Warranty Coverage Period				5 years