Finance receivables (Finance Revenues) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Apr. 30, 2012	Apr. 30, 2011	Apr. 30, 2012	Apr. 30, 2011
Finance revenues from on-balance sheet receivables:
Retail notes and finance leases revenue	$ 26	$ 39	$ 52	$ 76
Operating lease revenue	11	8	20	15
Gross finance revenues	67	83	135	156
Less: Intercompany revenues	(24)	(26)	(48)	(49)
Finance revenues	43	57	87	107
Off Balance Sheet Securitization Transactions [Member]
Finance revenues from on-balance sheet receivables:
Securitization income	0	4	0	2
Wholesale Portfolio [Member] \| Notes Receivable [Member]
Finance revenues from on-balance sheet receivables:
Finance revenues interest income	22	26	45	51
Retail And Wholesale Portfolios [Member] \| Accounts Receivable [Member]
Finance revenues from on-balance sheet receivables:
Finance revenues interest income	$ 8	$ 6	$ 18	$ 12

Finance Revenues From On Balance Sheet Receivables

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- Definition

Retail Notes And Finance Leases Revenue

+ References

No definition available.

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- Definition

The aggregate financial services revenue and operating interest income earned during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Interest generated from day to day operating activities of the business. This element represents a revenue generating activity and is therefore gross (before any related cost of revenue items).

+ References

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- Definition

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 19

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Topic 840

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- Definition

Proceeds from securitizations of receivables treated as collateralized borrowings, which are classified as financing transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Section 45

-Paragraph 14

-Subparagraph (b)

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- Definition

Revenues arising from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's' management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

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-Glossary Related Parties

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

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-Paragraph 1

-Subparagraph (SX 210.6-07.1(c))

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-Publisher SEC

-Name Regulation S-X (SX)

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