Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Section 45
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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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No definition available.

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Restructuring and Impairments - Schedule of Impairment Charges (Details) - USD ($) $ in Millions	9 Months Ended			12 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Restructuring Cost and Reserve [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)				$ 0	$ 0	$ 1
Other Asset Impairment Charges				14	13	26
Asset impairment charges				14	13	27
Brazilian Reporting Unit [Member]
Restructuring Cost and Reserve [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)						1
North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)						8
Asset impairment charges						$ 17
Pure Power Technologies [Member] \| North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment charges			$ 3
long-lived asset [Domain] \| North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment charges	$ 6	$ 5
Property Subject to Operating Lease [Member] \| North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment charges				$ 5	$ 8