| **Allowance for Doubtful Accounts - Schedule of Allowance for Retail, Wholesale, Trade & Other (Details) (USD $)In Millions, unless otherwise specified**                                                                                                                                                                                                                      | 3 Months Ended                                                                                                                                     | 6 Months Ended                                                                                                                                       |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------|
||
| **Allowance for Doubtful Accounts Receivable [Roll Forward]**                                                                                                                                                                                                                                                                                                                      |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| Allowance for doubtful accounts at beginning of period                                                                                                                                                                                                                                                                                                                             | $ 58us-gaap_FinancingReceivableAllowanceForCreditLosses                                                                                            | $ 60us-gaap_FinancingReceivableAllowanceForCreditLosses                                                                                              | $ 65us-gaap_FinancingReceivableAllowanceForCreditLosses |  | $ 60us-gaap_FinancingReceivableAllowanceForCreditLosses |  |
| Provision for doubtful accounts, net of recoveries                                                                                                                                                                                                                                                                                                                                 | 3us-gaap_ProvisionForLoanLeaseAndOtherLosses                                                                                                       | 4us-gaap_ProvisionForLoanLeaseAndOtherLosses                                                                                                         | 5us-gaap_ProvisionForLoanLeaseAndOtherLosses | [1] | 10us-gaap_ProvisionForLoanLeaseAndOtherLosses | [1] |
| Charge-off of accounts                                                                                                                                                                                                                                                                                                                                                             | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs                                                                                      | (5)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs                                                                                      | (4)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs | [2] | (7)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs | [2] |
| Allowance for doubtful accounts at end of period                                                                                                                                                                                                                                                                                                                                   | 58us-gaap_FinancingReceivableAllowanceForCreditLosses                                                                                              | 62us-gaap_FinancingReceivableAllowanceForCreditLosses                                                                                                | 58us-gaap_FinancingReceivableAllowanceForCreditLosses |  | 62us-gaap_FinancingReceivableAllowanceForCreditLosses |  |
| Loss on Contract Termination for Default                                                                                                                                                                                                                                                                                                                                           | 1us-gaap_LossOnContractTerminationForDefault                                                                                                       | 1us-gaap_LossOnContractTerminationForDefault                                                                                                         | 1us-gaap_LossOnContractTerminationForDefault |  | 1us-gaap_LossOnContractTerminationForDefault |  |
| Financing Receivable, Allowance for Credit Losses, Other                                                                                                                                                                                                                                                                                                                           | (3)nav_FinancingReceivableAllowanceforCreditLossesOther                                                                                            | 3nav_FinancingReceivableAllowanceforCreditLossesOther                                                                                                | (8)nav_FinancingReceivableAllowanceforCreditLossesOther |  | (1)nav_FinancingReceivableAllowanceforCreditLossesOther |  |
| Retail Portfolio [Member]                                                                                                                                                                                                                                                                                                                                                          |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| **Allowance for Doubtful Accounts Receivable [Roll Forward]**                                                                                                                                                                                                                                                                                                                      |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| Allowance for doubtful accounts at beginning of period                                                                                                                                                                                                                                                                                                                             | 23us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                  | 22us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                    | 24us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember |  | 21us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember |  |
| Provision for doubtful accounts, net of recoveries                                                                                                                                                                                                                                                                                                                                 | 3us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                           | 3us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                             | 5us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember | [1] | 7us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember | [1] |
| Charge-off of accounts                                                                                                                                                                                                                                                                                                                                                             | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember          | (3)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember          | (1)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember | [2] | (5)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember | [2] |
| Allowance for doubtful accounts at end of period                                                                                                                                                                                                                                                                                                                                   | 25us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                  | 22us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                    | 25us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember |  | 22us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember |  |
| Financing Receivable, Allowance for Credit Losses, Other                                                                                                                                                                                                                                                                                                                           | (1)nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                | 0nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember                    | (3)nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember |  | (1)nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_RetailPortfolioMember |  |
| Wholesale Portfolio [Member]                                                                                                                                                                                                                                                                                                                                                       |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| **Allowance for Doubtful Accounts Receivable [Roll Forward]**                                                                                                                                                                                                                                                                                                                      |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| Allowance for doubtful accounts at beginning of period                                                                                                                                                                                                                                                                                                                             | 3us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                | 2us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                  | 3us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember |  | 2us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember |  |
| Provision for doubtful accounts, net of recoveries                                                                                                                                                                                                                                                                                                                                 | 0us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                        | 0us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                          | 0us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember | [1] | 0us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember | [1] |
| Charge-off of accounts                                                                                                                                                                                                                                                                                                                                                             | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember       | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember         | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember | [2] | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember | [2] |
| Allowance for doubtful accounts at end of period                                                                                                                                                                                                                                                                                                                                   | 3us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                | 2us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                  | 3us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember |  | 2us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember |  |
| Financing Receivable, Allowance for Credit Losses, Other                                                                                                                                                                                                                                                                                                                           | 0nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember               | 0nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember                 | 0nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember |  | 0nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_WholesalePortfolioMember |  |
| Trade and Other Receivables [Member]                                                                                                                                                                                                                                                                                                                                               |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| **Allowance for Doubtful Accounts Receivable [Roll Forward]**                                                                                                                                                                                                                                                                                                                      |                                                                                                                                               |                                                                                                                                                 |   |  |   |  |
| Allowance for doubtful accounts at beginning of period                                                                                                                                                                                                                                                                                                                             | 32us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember         | 36us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember           | 38us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember |  | 37us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember |  |
| Provision for doubtful accounts, net of recoveries                                                                                                                                                                                                                                                                                                                                 | 0us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember                  | 1us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember                    | 0us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember | [1] | 3us-gaap_ProvisionForLoanLeaseAndOtherLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember | [1] |
| Charge-off of accounts                                                                                                                                                                                                                                                                                                                                                             | 0us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember | (2)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember | (3)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember | [2] | (2)us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember | [2] |
| Allowance for doubtful accounts at end of period                                                                                                                                                                                                                                                                                                                                   | 30us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember         | 38us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember           | 30us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember |  | 38us-gaap_FinancingReceivableAllowanceForCreditLosses/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember |  |
| Financing Receivable, Allowance for Credit Losses, Other                                                                                                                                                                                                                                                                                                                           | $ (2)nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember     | $ 3nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember         | $ (5)nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember |  | $ 0nav_FinancingReceivableAllowanceforCreditLossesOther/ nav_ReceivableInformationByPortfolioSegmentAxis= nav_TradeAndOtherReceivablesMember |  |
|                                                                                                                                                                                                                                                                                                                                                                                    |
| [1](A)[2]We repossess sold and leased vehicles on defaulted finance receivables and leases, and place them into Inventories. Losses recognized at the time of repossession and charged against the allowance for doubtful accounts were both less than $1 million, for the three and six months ended April 30, 2015, as well as for the three and six months ended April 30, 2014 |

| X                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Allowance for Credit Losses, Other
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A valuation allowance for financing receivables that are expected to be uncollectible.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524
+ Details**Name:**us-gaap_FinancingReceivableAllowanceForCreditLosses**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of direct write-downs of financing receivables charged against the allowance.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of the loss on termination of a contract for default.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 912 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6539154&loc=d3e52595-109384
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 9Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524
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| X                                                                                                                                                                 |
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| X                                                                                                                                                                    |
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