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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.

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Amount of costs incurred to date for the specified restructuring cost.

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Amount expected to be recognized in earnings for the specified restructuring cost.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Restructuring and Impairments - Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014	Jan. 31, 2014	Jan. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 6us-gaap_RestructuringCharges	$ 8us-gaap_RestructuringCharges	$ 9us-gaap_RestructuringCharges	$ 11us-gaap_RestructuringCharges
Asset impairment charges	1us-gaap_AssetImpairmentCharges	151us-gaap_AssetImpairmentCharges	8us-gaap_AssetImpairmentCharges	169us-gaap_AssetImpairmentCharges
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges		8
North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment charges					18
Minimum [Member] \| Chatham [Member] \| North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	0		0
Maximum [Member] \| Chatham [Member] \| North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost	60		60
Maximum [Member] \| Indianapolis and Waukesha Foundry [Member] \| North America Truck [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	12		12			13
Brazilian Reporting Unit [Member]
Restructuring Cost and Reserve [Line Items]
Asset impairment charges		149
Goodwill, Impairment Loss	0	142	0	142
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 0	$ 7	$ 0	$ 7