| **Segment Reporting - Summary of Segment Operations (Details) (USD $)In Millions, unless otherwise specified** | 3 Months Ended                                                                                                                    | 6 Months Ended                     |
|----------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------|------------------------------------|
||
| **Segment Reporting Information [Line Items]**                                                                 |                                                                                                                              |                               |   |   |   |
| External sales and revenues, net                                                                               | $ 2,693nav_Externalsalesandrevenuesnet                                                                                            |                               | $ 2,746nav_Externalsalesandrevenuesnet | $ 5,114nav_Externalsalesandrevenuesnet | $ 4,954nav_Externalsalesandrevenuesnet |
| Sales and revenues, net                                                                                        | 2,693us-gaap_Revenues                                                                                                             |                               | 2,746us-gaap_Revenues | 5,114us-gaap_Revenues | 4,954us-gaap_Revenues |
| Loss from continuing operations, net of tax                                                                    | (64)us-gaap_IncomeLossFromContinuingOperations                                                                                    |                               | (298)us-gaap_IncomeLossFromContinuingOperations | (106)us-gaap_IncomeLossFromContinuingOperations | (547)us-gaap_IncomeLossFromContinuingOperations |
| Income tax expense                                                                                             | (18)us-gaap_IncomeTaxExpenseBenefit                                                                                               |                               | (23)us-gaap_IncomeTaxExpenseBenefit | (25)us-gaap_IncomeTaxExpenseBenefit | (11)us-gaap_IncomeTaxExpenseBenefit |
| Interest expense                                                                                               | 75us-gaap_InterestExpense                                                                                                         |                               | 74us-gaap_InterestExpense | 152us-gaap_InterestExpense | 156us-gaap_InterestExpense |
| Equity in income of non-consolidated affiliates                                                                | 1us-gaap_IncomeLossFromEquityMethodInvestments                                                                                    |                               | 3us-gaap_IncomeLossFromEquityMethodInvestments | 3us-gaap_IncomeLossFromEquityMethodInvestments | 3us-gaap_IncomeLossFromEquityMethodInvestments |
| Capital expenditures                                                                                           | 28us-gaap_PaymentsToAcquirePropertyPlantAndEquipment                                                                              |                               | 29us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | 45us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | 50us-gaap_PaymentsToAcquirePropertyPlantAndEquipment |
| Intersegment sales and revenues                                                                                | 0nav_Intersegmentsalesandrevenues                                                                                                 | 35nav_Intersegmentsalesandrevenues | 0nav_Intersegmentsalesandrevenues | 0nav_Intersegmentsalesandrevenues | 0nav_Intersegmentsalesandrevenues |
| Segment Profit Loss                                                                                            | (46)nav_SegmentProfitLoss                                                                                                         |                               | (275)nav_SegmentProfitLoss | (81)nav_SegmentProfitLoss | (536)nav_SegmentProfitLoss |
| Depreciation, Depletion and Amortization                                                                       | 74us-gaap_DepreciationDepletionAndAmortization                                                                                    |                               | 99us-gaap_DepreciationDepletionAndAmortization | 153us-gaap_DepreciationDepletionAndAmortization | 185us-gaap_DepreciationDepletionAndAmortization |
| North America Truck [Member]                                                                                   |                                                                                                                              |                               |   |   |   |
| **Segment Reporting Information [Line Items]**                                                                 |                                                                                                                              |                               |   |   |   |
| External sales and revenues, net                                                                               | 1,933nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                          |                               | 1,829nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 3,564nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 3,220nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| Sales and revenues, net                                                                                        | 1,966us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                         |                               | 1,889us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 3,636us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 3,340us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| Loss from continuing operations, net of tax                                                                    | (51)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                |                               | (129)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | (69)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | (337)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| Income tax expense                                                                                             | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                              |                               | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| 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 |
| Equity in income of non-consolidated affiliates                                                                | 1us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                |                               | 1us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 3us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 2us-gaap_IncomeLossFromEquityMethodInvestments/ 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 |
| Intersegment sales and revenues                                                                                | 33nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                            |                               | 60nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 72nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 120nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| Segment Profit Loss                                                                                            | (51)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                                     |                               | (129)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | (69)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | (337)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| Depreciation, Depletion and Amortization                                                                       | 47us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember                |                               | 71us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 99us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember | 129us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaTruckMember |
| North America Parts [Member]                                                                                   |                                                                                                                              |                               |   |   |   |
| **Segment Reporting Information [Line Items]**                                                                 |                                                                                                                              |                               |   |   |   |
| External sales and revenues, net                                                                               | 607nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                            |                               | 614nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 1,221nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 1,188nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Sales and revenues, net                                                                                        | 613us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                                           |                               | 630us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 1,239us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 1,216us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Loss from continuing operations, net of tax                                                                    | 133us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                 |                               | 133us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 278us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 241us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Income tax expense                                                                                             | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                              |                               | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Interest expense                                                                                               | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                                      |                               | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Equity in income of non-consolidated affiliates                                                                | 1us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                |                               | 1us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 2us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 2us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Capital expenditures                                                                                           | 0us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember           |                               | 1us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 0us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 5us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Intersegment sales and revenues                                                                                | 6nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                             |                               | 16nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 18nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 28nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Segment Profit Loss                                                                                            | 133nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                                      |                               | 133nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 278nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 241nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Depreciation, Depletion and Amortization                                                                       | 4us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember                 |                               | 4us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 7us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember | 8us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_NorthAmericaPartsMember |
| Global Operations [Member]                                                                                     |                                                                                                                              |                               |   |   |   |
| **Segment Reporting Information [Line Items]**                                                                 |                                                                                                                              |                               |   |   |   |
| External sales and revenues, net                                                                               | 115nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                             |                               | 265nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 253nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 469nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Sales and revenues, net                                                                                        | 130us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                                            |                               | 271us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 282us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 483us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Loss from continuing operations, net of tax                                                                    | 1us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                    |                               | (162)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | (14)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | (197)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Income tax expense                                                                                             | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                               |                               | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Interest expense                                                                                               | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                                       |                               | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 0us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Equity in income of non-consolidated affiliates                                                                | (1)us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember               |                               | 1us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | (2)us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | (1)us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Capital expenditures                                                                                           | 1us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember            |                               | 1us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 3us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 4us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Intersegment sales and revenues                                                                                | 15nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                             |                               | 6nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 29nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 14nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Segment Profit Loss                                                                                            | 1nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                                         |                               | (162)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | (14)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | (197)nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Depreciation, Depletion and Amortization                                                                       | 5us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember                  |                               | 6us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 12us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember | 14us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_GlobalOperationsMember |
| Financial Services Operations [Member]                                                                         |                                                                                                                              |                               |   |   |   |
| **Segment Reporting Information [Line Items]**                                                                 |                                                                                                                              |                               |   |   |   |
| External sales and revenues, net                                                                               | 35nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                   |                               | 38nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 71nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 77nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Sales and revenues, net                                                                                        | 60us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                                  |                               | 57us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 120us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 112us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Loss from continuing operations, net of tax                                                                    | 22us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember        |                               | 24us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 46us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 47us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Income tax expense                                                                                             | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                    |                               | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 0us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Interest expense                                                                                               | 18us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                           |                               | 17us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 38us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 34us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Equity in income of non-consolidated affiliates                                                                | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember      |                               | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Capital expenditures                                                                                           | 2us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |                               | 0us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 2us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 1us-gaap_PaymentsToAcquirePropertyPlantAndEquipment/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Investment Income, Interest                                                                                    | 44us-gaap_InvestmentIncomeInterest/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                  |                               | 42us-gaap_InvestmentIncomeInterest/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 89us-gaap_InvestmentIncomeInterest/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 82us-gaap_InvestmentIncomeInterest/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Intersegment sales and revenues                                                                                | 25nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                  |                               | 19nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 49nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 35nav_Intersegmentsalesandrevenues/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Segment Profit Loss                                                                                            | 22nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember                             |                               | 24nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 46nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 47nav_SegmentProfitLoss/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Depreciation, Depletion and Amortization                                                                       | 12us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember      |                               | 11us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 24us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember | 21us-gaap_DepreciationDepletionAndAmortization/ us-gaap_StatementBusinessSegmentsAxis= nav_FinancialServicesOperationsMember |
| Corporate And Eliminations [Member]                                                                            |                                                                                                                              |                               |   |   |   |
| **Segment Reporting Information [Line Items]**                                                                 |                                                                                                                              |                               |   |   |   |
| External sales and revenues, net                                                                               | 3nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember                       |                               | 0nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | 5nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | 0nav_Externalsalesandrevenuesnet/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember |
| Sales and revenues, net                                                                                        | (76)us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember                                   |                               | (101)us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | (163)us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | (197)us-gaap_Revenues/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember |
| Loss from continuing operations, net of tax                                                                    | (169)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember        |                               | (164)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | (347)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | (301)us-gaap_IncomeLossFromContinuingOperations/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember |
| Income tax expense                                                                                             | (18)us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember                    |                               | (23)us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | (25)us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | (11)us-gaap_IncomeTaxExpenseBenefit/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember |
| Interest expense                                                                                               | 57us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember                              |                               | 57us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | 114us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | 122us-gaap_InterestExpense/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember |
| Equity in income of non-consolidated affiliates                                                                | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember         |                               | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember | 0us-gaap_IncomeLossFromEquityMethodInvestments/ us-gaap_StatementBusinessSegmentsAxis= nav_CorporateAndEliminationsMember |
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| - Definition
External sales and revenues, net
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| - Definition
Intersegment sales and revenues
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| - Definition
Amount of profit or loss recognized by the reportable segment.
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| - Definition
The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.
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| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
+ References
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| - Definition
Amount of the cost of borrowed funds accounted for as interest expense.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.
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| - 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.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).
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