| **Stockholders' Deficit Accumulated Other Comprehensive Income (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions** | 3 Months Ended |           |
|---------------------------------------------------------------------------------------------------------------------------------------------|----------------|-----------|
||
| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]**                                                                |           |      |   |
| Accumulated Other Comprehensive Loss, Beginning Balance                                                                                     | $ (2,640)      | $ (2,601) |   |
| Other comprehensive loss before reclassifications                                                                                           | (12)           | (33)      |   |
| Amounts reclassified out of accumulated other comprehensive loss                                                                            | 35             | 33        |   |
| Net current-period other comprehensive income (loss)                                                                                        | 23             | 0         |   |
| Accumulated Other Comprehensive Loss, Ending Balance                                                                                        | (2,617)        | (2,601)   |   |
| **Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]**                                     |           |      |   |
| Tax expense                                                                                                                                 | (4)            | 5         |   |
| Net income (loss) attributable to Navistar International Corporation                                                                        | $ (62)         | (33)      |   |
| Common stock, shares authorized                                                                                                             | 220            |      | 220 |
| Common stock, par value                                                                                                                     | $ 0.10         |      | $ 0.10 |
| Accumulated Net Unrealized Investment Gain (Loss) [Member]                                                                                  |           |      |   |
| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]**                                                                |           |      |   |
| Accumulated Other Comprehensive Loss, Beginning Balance                                                                                     | $ 1            | 1         |   |
| Other comprehensive loss before reclassifications                                                                                           | 0              | 0         |   |
| Amounts reclassified out of accumulated other comprehensive loss                                                                            | 0              | 0         |   |
| Net current-period other comprehensive income (loss)                                                                                        | 0              | 0         |   |
| Accumulated Other Comprehensive Loss, Ending Balance                                                                                        | 1              | 1         |   |
| Accumulated Translation Adjustment [Member]                                                                                                 |           |      |   |
| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]**                                                                |           |      |   |
| Accumulated Other Comprehensive Loss, Beginning Balance                                                                                     | (280)          | (287)     |   |
| Other comprehensive loss before reclassifications                                                                                           | (12)           | (33)      |   |
| Amounts reclassified out of accumulated other comprehensive loss                                                                            | 0              | 0         |   |
| Net current-period other comprehensive income (loss)                                                                                        | (12)           | (33)      |   |
| Accumulated Other Comprehensive Loss, Ending Balance                                                                                        | (292)          | (320)     |   |
| Pension Benefits                                                                                                                            |           |      |   |
| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]**                                                                |           |      |   |
| Accumulated Other Comprehensive Loss, Beginning Balance                                                                                     | (2,361)        | (2,315)   |   |
| Other comprehensive loss before reclassifications                                                                                           | 0              | 0         |   |
| Amounts reclassified out of accumulated other comprehensive loss                                                                            | 35             | 33        |   |
| Net current-period other comprehensive income (loss)                                                                                        | 35             | 33        |   |
| Accumulated Other Comprehensive Loss, Ending Balance                                                                                        | (2,326)        | (2,282)   |   |
| Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension Benefits                                                  |           |      |   |
| **Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax [Abstract]**                                     |           |      |   |
| Amortization of actuarial loss                                                                                                              | 35             | 33        |   |
| Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent                                                              | $ 35           | $ 33      |   |
| Volkswagen Truck and Bus GmbH [Member]                                                                                                      |           |      |   |
| **Accumulated Other Comprehensive Income (Loss) [Line Items]**                                                                              |           |      |   |
| Share Price                                                                                                                                 | $ 15.76        |      |   |
| Stock Issued During Period, Value, New Issues                                                                                               | $ 256          |      |   |

| X                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.
+ References
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| - Definition
Face amount or stated value per share of common stock.
+ References
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| - Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws.
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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
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
+ References
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| - Definition
Amount after tax, before reclassification adjustments of other comprehensive income (loss).
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| - Definition
Amount after tax and reclassification adjustments of other comprehensive income (loss).
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans.
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Amount after tax of reclassification adjustments of other comprehensive income (loss).
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| - Definition
Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.
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Price of a single share of a number of saleable stocks of a company.
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| - Definition
Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.
+ References
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