| **Summary of Significant Accounting Policies - Narrative (Details) $ in Millions**              | 3 Months Ended | 9 Months Ended |         |
|-------------------------------------------------------------------------------------------------|----------------|----------------|---------|
||
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Costs of products sold                                                                          | $ 1,757        |           | $ 2,172 |   | $ 5,068 | $ 6,577 |   |
| Net loss attributable to Navistar International Corporation                                     | $ (34)         |           | (28)    |   | (63) | (134) |   |
| Number Of Segments | segments                                                                   | 4              |           |    |   |   |   |   |
| Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)                          | $ 1            |           | 3       |   | 1 | 3 |   |
| Goodwill                                                                                        | 38             |           |    |   | 38 |   | $ 38 |
| Sales of manufactured products, net                                                             | 2,052          |           | 2,501   |   | 5,946 | 7,544 |   |
| Depreciation, Depletion and Amortization                                                        | 53             |           | 68      |   | 164 | 221 |   |
| Interest expense                                                                                | 84             |           | 75      |   | 246 | 227 |   |
| Capital expenditures                                                                            | $ 30           |           | 27      |   | 83 | 72 |   |
| Proceeds from financed lease obligations                                                        |           |           |    |   | 17 | 26 |   |
| Product Warranty Accrual, Preexisting, Increase (Decrease)                                      |           |           |    |   | $ 70 | (38) |   |
| Unionized Employees Concentration Risk [Member] | Number Of Employees Hourly Workers [Member]   |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Concentration Risk Number Of Employees | employees                                              | 5,400          |           |    |   | 5,400 |   |   |
| concentration risk number of employees percentage                                               | 82.00%         |           |    |   | 82.00% |   |   |
| Unionized Employees Concentration Risk [Member] | Number of Employees Salaried Workers [Member] |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Concentration Risk Number Of Employees | employees                                              | 300            |           |    |   | 300 |   |   |
| concentration risk number of employees percentage                                               | 6.00%          |           |    |   | 6.00% |   |   |
| Brazilian Reporting Unit [Member]                                                               |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)                          | $ 1            |           | 3       |   |   |   |   |
| Indefinite-Lived Intangible Assets (Excluding Goodwill)                                         |           |           | 24      |   |   | 24 |   |
| Product Warranty Accrual [Member]                                                               |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Product Warranty Accrual, Preexisting, Increase (Decrease)                                      |           | $ 46           |    | $ (57) |   |   |   |
| North America Truck [Member]                                                                    |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)                          | 11             |           |    | $ 7 |   |   |   |
| Depreciation, Depletion and Amortization                                                        | 29             |           | 40      |   | $ 92 | 139 |   |
| Interest expense                                                                                | 0              |           | 0       |   | 0 | 0 |   |
| Capital expenditures                                                                            | 26             |           | 20      |   | 70 | 58 |   |
| Extended Warranty Programs [Member]                                                             |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Deferred Revenue, Revenue Recognized                                                            | 37             |           | 40      |   | 113 | $ 115 |   |
| Deferred Revenue                                                                                | $ 345          |           |    |   | $ 345 |   | $ 401 |
| Discontinued Operations [Member] | Product Warranty Accrual [Member]                            |           |           |    |   |   |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |    |   |   |   |   |
| Product Warranty Accrual, Preexisting, Increase (Decrease)                                      |           |           | $ 2     |   |   |   |   |

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Proceeds from finance lease obligations
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| - Definition
Total costs related to goods produced and sold during the reporting period.
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| - 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.
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| - Definition
Amount of revenue recognized that was previously reported as deferred or unearned revenue.
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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.
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| - Definition
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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| - 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.
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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.
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| - Definition
Amount of the cost of borrowed funds accounted for as interest expense.
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| - Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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| - 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.
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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 increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.
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| - Definition
Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.
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