| **Finance receivables (Tables)**                                | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|-----------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Receivables [Abstract]**                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Finance receivables by major classification                     | Our finance receivables by major classification are as follows: April 30, 2012 October 31, 2011(in millions)   Retail portfolio$1,384 $1,613Wholesale portfolio1,284 1,334Total finance receivables2,668 2,947Less: Allowance for doubtful accounts28 34Total finance receivables, net2,640 2,913Less: Current portion, net(A)2,066 2,198Noncurrent portion, net$574 $715_________________________(A)The current portion of finance receivables is computed based on contractual maturities. Actual cash collections typically vary from the contractual cash flows because of prepayments, extensions, delinquencies, credit losses, and renewals. |
| Components of available wholesale note trust funding facilities | Components of available wholesale note trust funding facilities were as follows: Maturity April 30, 2012 October 31, 2011(in millions)     Variable funding notes ("VFN")July 2012 $500 $500Investor notesOctober 2012 350 350Investor notesOctober 2013 224 —Investor notesJanuary 2012 — 250Total wholesale note funding  $1,074 $1,100                                                                                                                                                                                                                                                       |
| Finance revenues derived from receivables                       | Finance revenues consist of the following: Three Months Ended April 30, Six Months Ended April 30, 2012 2011 2012 2011(in millions)       Retail notes and finance leases revenue$26 $39 $52 $76Operating lease revenue11 8 20 15Wholesale notes interest22 26 45 51Retail and wholesale accounts interest8 6 18 12Securitization income— 4 — 2Gross finance revenues67 83 135 156Less: Intercompany revenues(24) (26) (48) (49)Finance revenues$43 $57 $87 $107                                                     |

| X                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Components Of Available Wholesale Note Trust Funding Facilities [Table Text Block]
+ References
No definition available.
+ Details**Name:**nav_ComponentsOfAvailableWholesaleNoteTrustFundingFacilitiesTableTextBlock**Namespace Prefix:**nav_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Finance Revenues Derived From Receivables [Table Text Block]
+ References
No definition available.
+ Details**Name:**nav_FinanceRevenuesDerivedFromReceivablesTableTextBlock**Namespace Prefix:**nav_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_ReceivablesAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 3, 4 -Article 5Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3,4) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
+ Details**Name:**us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |