| **Summary of Significant Accounting Policies - Narrative (Details)**                            | 3 Months Ended | 9 Months Ended |               |
|-------------------------------------------------------------------------------------------------|----------------|----------------|---------------|
||
| **Accounting Policies [Line Items]**                                                            |           |           |          |   |   |
| Less: Intercompany revenues                                                                     | $ 33,000,000   | $ 36,000,000   | $ 114,000,000 | $ 78,000,000 |   |
| Costs of products sold                                                                          | 2,096,000,000  | 1,803,000,000  | 5,615,000,000 | 4,949,000,000 |   |
| Net loss attributable to Navistar International Corporation                                     | $ 170,000,000  | 37,000,000     | $ 152,000,000 | (105,000,000) |   |
| Number Of Segments | segments                                                                   | 4              |           | 4             |   |   |
| Goodwill                                                                                        | $ 38,000,000   |           | $ 38,000,000  |   | $ 38,000,000 |
| Sales of manufactured products, net                                                             | 2,566,000,000  | 2,178,000,000  | 6,815,000,000 | 5,870,000,000 |   |
| Interest expense                                                                                | 82,000,000     | 91,000,000     | 240,000,000   | 262,000,000 |   |
| Capital expenditures                                                                            | 26,000,000     | 27,000,000     | 79,000,000    | 93,000,000 |   |
| Proceeds from finance lease obligations                                                         |           |           | 48,000,000    | 49,000,000 |   |
| Product Warranty Accrual, Preexisting, Increase (Decrease)                                      |           |           | $ (4,000,000) | (4,000,000) |   |
| Document Type                                                                                   |           |           | 10-Q          |   |   |
| Costs and Expenses, Related Party                                                               | 2,000,000      | 2,000,000      | $ 21,000,000  | 4,000,000 |   |
| Accounts Receivable, Related Parties                                                            | 11,000,000     |           | 11,000,000    |   | 13,000,000 |
| Accounts Payable, Related Parties                                                               | 20,000,000     |           | 20,000,000    |   | 5,000,000 |
| Inventory, Gross                                                                                | $ 191,000,000  |           | $ 191,000,000 |   | 206,000,000 |
| Unionized Employees Concentration Risk [Member] | Number Of Employees Hourly Workers [Member]   |           |           |          |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |          |   |   |
| Concentration Risk Number Of Employees | employees                                              | 7,800          |           | 7,800         |   |   |
| concentration risk number of employees percentage                                               | 98.00%         |           | 98.00%        |   |   |
| Unionized Employees Concentration Risk [Member] | Number of Employees Salaried Workers [Member] |           |           |          |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |          |   |   |
| Concentration Risk Number Of Employees | employees                                              | 700            |           | 700           |   |   |
| concentration risk number of employees percentage                                               | 13.00%         |           | 13.00%        |   |   |
| North America Truck [Member]                                                                    |           |           |          |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |          |   |   |
| Interest expense                                                                                | $ 0            | 0              | $ 0           | 0 |   |
| Capital expenditures                                                                            | 19,000,000     | 21,000,000     | 74,000,000    | 78,000,000 |   |
| Extended Warranty Programs [Member]                                                             |           |           |          |   |   |
| **Accounting Policies [Line Items]**                                                            |           |           |          |   |   |
| Deferred Revenue, Revenue Recognized                                                            | 24,000,000     | $ 28,000,000   | 80,000,000    | $ 109,000,000 |   |
| Deferred Revenue                                                                                | $ 248,000,000  |           | $ 248,000,000 |   | $ 271,000,000 |

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Amount for accounts payable to related parties.
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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.
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Total costs related to goods produced and sold during the reporting period.
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Costs of sales and operating expenses for the period incurred from transactions with related parties.
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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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Amount of revenue recognized that was previously reported as deferred or unearned revenue.
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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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Amount of the cost of borrowed funds accounted for as interest expense.
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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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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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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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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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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.
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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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