Allowance for Doubtful Accounts - Schedule of Allowance Aging Analysis (Details) (USD $) In Millions, unless otherwise specified	Oct. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Finance Receivables, Current	$ 1,976nav_FinanceReceivablesCurrent
30-90 days past due	66
Over 90 days past due	23
Total finance receivables	2,065
Retail Portfolio [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Finance Receivables, Current	643
30-90 days past due	64
Over 90 days past due	19
Total finance receivables	726
Wholesale Portfolio [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Finance Receivables, Current	1,333
30-90 days past due	2
Over 90 days past due	4
Total finance receivables	$ 1,339

'Reflects carrying amount of all categories of loans and leases held in portfolio, net of unearned income and the allowance for losses on loans and leases, due from customers, clients, lessees, borrowers, or others within one year of the balance sheet date (or the normal operating cycle, whichever is longer).

No definition available.

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- Definition

Financing Receivables Recorded Investment 30 To 90 Days Past Due

+ References

No definition available.

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953401-111524

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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