| **Summary of Significant Accounting Policies - Narrative (Details) (USD $)In Millions, unless otherwise specified** | 3 Months Ended                                                                                                                                                                                                                      | 6 Months Ended                                                                                                                                                                              | 3 Months Ended                                                                                                                                                                                                                      |                                                                                                                                |
|---------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------|
||
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Net loss attributable to Navistar International Corporation                                                         | $ (64)us-gaap_NetIncomeLoss                                                                                                                                                                                                         | $ (297)us-gaap_NetIncomeLoss                                                                                                                                                                | $ (106)us-gaap_NetIncomeLoss                                                                                                                                                                                                        | $ (545)us-gaap_NetIncomeLoss                                                                                                   |   |   |   |
| Number Of Segments                                                                                                  |                                                                                                                                                                                                                                |                                                                                                                                                                                        | 4us-gaap_NumberOfReportableSegments                                                                                                                                                                                                 |                                                                                                                           |   |   |   |
| Sales of manufactured products, net                                                                                 | 2,658us-gaap_SalesRevenueGoodsNet                                                                                                                                                                                                   | 2,708us-gaap_SalesRevenueGoodsNet                                                                                                                                                           | 5,043us-gaap_SalesRevenueGoodsNet                                                                                                                                                                                                   | 4,877us-gaap_SalesRevenueGoodsNet                                                                                              |   |   |   |
| Interest expense                                                                                                    | 75us-gaap_InterestExpense                                                                                                                                                                                                           | 74us-gaap_InterestExpense                                                                                                                                                                   | 152us-gaap_InterestExpense                                                                                                                                                                                                          | 156us-gaap_InterestExpense                                                                                                     |   |   |   |
| Capital expenditures                                                                                                | 28us-gaap_PaymentsToAcquirePropertyPlantAndEquipment                                                                                                                                                                                | 29us-gaap_PaymentsToAcquirePropertyPlantAndEquipment                                                                                                                                        | 45us-gaap_PaymentsToAcquirePropertyPlantAndEquipment                                                                                                                                                                                | 50us-gaap_PaymentsToAcquirePropertyPlantAndEquipment                                                                           |   |   |   |
| Proceeds from financed lease obligations                                                                            |                                                                                                                                                                                                                                |                                                                                                                                                                                        | 20nav_ProceedsFromFinanceLeaseObligations                                                                                                                                                                                           | 34nav_ProceedsFromFinanceLeaseObligations                                                                                      |   |   |   |
| Product Warranty Accrual, Preexisting, Increase (Decrease)                                                          |                                                                                                                                                                                                                                |                                                                                                                                                                                        | (39)us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease                                                                                                                                                                       | 94us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease                                                                    |   |   |   |
| Unionized Employees Concentration Risk [Member] | Number Of Employees Hourly Workers [Member]                       |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Concentration Risk Number Of Employees                                                                              | 6,200nav_ConcentrationRiskNumberOfEmployees/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesHourlyWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember             |                                                                                                                                                                                        | 6,200nav_ConcentrationRiskNumberOfEmployees/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesHourlyWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember             |                                                                                                                           |   |   |   |
| concentration risk number of employees percentage                                                                   | 73.00%nav_ConcentrationRiskNumberOfEmployeesPercentage/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesHourlyWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember  |                                                                                                                                                                                        | 73.00%nav_ConcentrationRiskNumberOfEmployeesPercentage/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesHourlyWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember  |                                                                                                                           |   |   |   |
| Unionized Employees Concentration Risk [Member] | Number of Employees Salaried Workers [Member]                     |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Concentration Risk Number Of Employees                                                                              | 300nav_ConcentrationRiskNumberOfEmployees/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesSalariedWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember             |                                                                                                                                                                                        | 300nav_ConcentrationRiskNumberOfEmployees/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesSalariedWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember             |                                                                                                                           |   |   |   |
| concentration risk number of employees percentage                                                                   | 5.00%nav_ConcentrationRiskNumberOfEmployeesPercentage/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesSalariedWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember |                                                                                                                                                                                        | 5.00%nav_ConcentrationRiskNumberOfEmployeesPercentage/ us-gaap_ConcentrationRiskByBenchmarkAxis= nav_NumberOfEmployeesSalariedWorkersMember/ us-gaap_ConcentrationRiskByTypeAxis= us-gaap_UnionizedEmployeesConcentrationRiskMember |                                                                                                                           |   |   |   |
| Brazilian Reporting Unit [Member]                                                                                   |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)                                              | 0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                                                                      | 7us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                              | 0us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                                                                      | 7us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember |   |   |   |
| Indefinite-Lived Intangible Assets (Excluding Goodwill)                                                             |                                                                                                                                                                                                                                | 43us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                                         |                                                                                                                                                                                                                                | 43us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember            |   |   |   |
| Goodwill, Impairment Loss                                                                                           | 0us-gaap_GoodwillImpairmentLoss/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                                                                                                            | 142us-gaap_GoodwillImpairmentLoss/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                                                                  | 0us-gaap_GoodwillImpairmentLoss/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                                                                                                                            | 142us-gaap_GoodwillImpairmentLoss/ nav_ReportingUnitAxis= nav_BrazilianReportingUnitMember                                     |   |   |   |
| Product Warranty Accrual [Member]                                                                                   |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Product Warranty Accrual, Preexisting, Increase (Decrease)                                                          |                                                                                                                                                                                                                                | 42us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease/ us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmountAxis= nav_ProductWarrantyAccrualMember |                                                                                                                                                                                                                                |                                                                                                                           | (57)us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease/ us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmountAxis= nav_ProductWarrantyAccrualMember | 52us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease/ us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmountAxis= nav_ProductWarrantyAccrualMember |   |
| North America Truck [Member]                                                                                        |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Interest expense                                                                                                    | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                                                                                                                        | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                                                                                | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                                                                                                                        | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                   |   |   |   |
| Capital expenditures                                                                                                | 24us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                                                                                            | 26us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                                                    | 38us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                                                                                            | 38us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember       |   |   |   |
| Extended Warranty Programs [Member]                                                                                 |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| **Accounting Policies [Line Items]**                                                                                |                                                                                                                                                                                                                                |                                                                                                                                                                                        |                                                                                                                                                                                                                                |                                                                                                                           |   |   |   |
| Deferred Revenue, Revenue Recognized                                                                                | 38us-gaap_DeferredRevenueRevenueRecognized/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember                                                                                                          | 33us-gaap_DeferredRevenueRevenueRecognized/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember                                                                  | 75us-gaap_DeferredRevenueRevenueRecognized/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember                                                                                                          | 60us-gaap_DeferredRevenueRevenueRecognized/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember     |   |   |   |
| Deferred Revenue                                                                                                    | $ 425us-gaap_DeferredRevenue/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember                                                                                                                        |                                                                                                                                                                                        | $ 425us-gaap_DeferredRevenue/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember                                                                                                                        |                                                                                                                           |   |   | $ 437us-gaap_DeferredRevenue/ us-gaap_DeferredRevenueArrangementTypeAxis= nav_ExtendedWarrantyProgramsMember |

| X                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**nav_AccountingPoliciesLineItems**Namespace Prefix:**nav_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Concentration Risk Number Of Employees
+ References
No definition available.
+ Details**Name:**nav_ConcentrationRiskNumberOfEmployees**Namespace Prefix:**nav_**Data Type:**xbrli:decimalItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
concentration risk number of employees percentage
+ References
No definition available.
+ Details**Name:**nav_ConcentrationRiskNumberOfEmployeesPercentage**Namespace Prefix:**nav_**Data Type:**num:percentItemType**Balance Type:**na**Period Type:**instant |
| X                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Proceeds from finance lease obligations
+ References
No definition available.
+ Details**Name:**nav_ProceedsFromFinanceLeaseObligations**Namespace Prefix:**nav_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 13 -Section AReference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response) -URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780
+ Details**Name:**us-gaap_DeferredRevenue**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 13.A.4(a).Q1) -URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 13 -Section A
+ Details**Name:**us-gaap_DeferredRevenueRevenueRecognized**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ 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 (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267
+ Details**Name:**us-gaap_GoodwillImpairmentLoss**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275
+ Details**Name:**us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275
+ Details**Name:**us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of the cost of borrowed funds accounted for as interest expense.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.9) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 9 -Article 9
+ Details**Name:**us-gaap_InterestExpense**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=6519514Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=6518256Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.19) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.18) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.22) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9
+ Details**Name:**us-gaap_NetIncomeLoss**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.
+ References
No definition available.
+ Details**Name:**us-gaap_NumberOfReportableSegments**Namespace Prefix:**us-gaap_**Data Type:**xbrli:integerItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585
+ Details**Name:**us-gaap_PaymentsToAcquirePropertyPlantAndEquipment**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard and extended product warranties (including adjustments for changes in estimates).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph ((c)(4)) -URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249
+ Details**Name:**us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(a)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5
+ Details**Name:**us-gaap_SalesRevenueGoodsNet**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**duration |
| X                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**nav_ReportingUnitAxis=nav_BrazilianReportingUnitMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_ConcentrationRiskByTypeAxis=us-gaap_UnionizedEmployeesConcentrationRiskMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_DeferredRevenueArrangementTypeAxis=nav_ExtendedWarrantyProgramsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmountAxis=nav_ProductWarrantyAccrualMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**us-gaap_StatementBusinessSegmentsAxis=nav_NorthAmericaTruckMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |