| **Segment Reporting - Summary of Segment Assets (Details) - USD ($) $ in Millions** | 3 Months Ended | 9 Months Ended |         |
|-------------------------------------------------------------------------------------|----------------|----------------|---------|
||
| **Segment Reporting Information [Line Items]**                                      |           |           |    |   |   |
| External sales and revenues, net                                                    | $ 1,675        | $ 3,042        | $ 5,438 | $ 8,471 |   |
| Segment Assets                                                                      | 6,675          |           | 6,675   |   | $ 6,917 |
| Intersegment sales and revenues                                                     | 0              | 0              | 0       | 0 |   |
| Sales and revenues, net                                                             | 1,675          | 3,042          | 5,438   | 8,471 |   |
| Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent        | (37)           | 156            | (111)   | 119 |   |
| Income Tax Expense (Benefit)                                                        | 8              | 29             | 10      | 9 |   |
| Segment Profit Loss                                                                 | (29)           | 185            | (101)   | 128 |   |
| Depreciation, Depletion and Amortization                                            | 47             | 47             | 146     | 144 |   |
| Interest expense                                                                    | 71             | 76             | 199     | 243 |   |
| Equity in income of non-consolidated affiliates                                     | 2              | 1              | 0       | 4 |   |
| Capital expenditures                                                                | 25             | 24             | 115     | 90 |   |
| North America Truck [Member]                                                        |           |           |    |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |    |   |   |
| External sales and revenues, net                                                    | 1,177          | 2,342          | 3,800   | 6,405 |   |
| Segment Assets                                                                      | 1,721          |           | 1,721   |   | 1,705 |
| Intersegment sales and revenues                                                     | 26             | 45             | 34      | 75 |   |
| Sales and revenues, net                                                             | 1,177          | 2,342          | 3,800   | 6,405 |   |
| Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent        | (22)           | 167            | (131)   | 183 |   |
| Income Tax Expense (Benefit)                                                        | 0              | 0              | 0       | 0 |   |
| Segment Profit Loss                                                                 | (22)           | 167            | (131)   | 183 |   |
| Depreciation, Depletion and Amortization                                            | 27             | 26             | 83      | 78 |   |
| Interest expense                                                                    | 0              | 0              | 0       | 0 |   |
| Equity in income of non-consolidated affiliates                                     | 2              | 0              | (1)     | 3 |   |
| Capital expenditures                                                                | 18             | 17             | 93      | 69 |   |
| North America Parts [Member]                                                        |           |           |    |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |    |   |   |
| External sales and revenues, net                                                    | 413            | 569            | 1,347   | 1,693 |   |
| Segment Assets                                                                      | 641            |           | 641     |   | 688 |
| Intersegment sales and revenues                                                     | 1              | 2              | 3       | 5 |   |
| Sales and revenues, net                                                             | 413            | 569            | 1,347   | 1,693 |   |
| Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent        | 97             | 149            | 319     | 437 |   |
| Income Tax Expense (Benefit)                                                        | 0              | 0              | 0       | 0 |   |
| Segment Profit Loss                                                                 | 97             | 149            | 319     | 437 |   |
| Depreciation, Depletion and Amortization                                            | 1              | 1              | 5       | 4 |   |
| Interest expense                                                                    | 0              | 0              | 0       | 0 |   |
| Equity in income of non-consolidated affiliates                                     | 0              | 1              | 1       | 2 |   |
| Capital expenditures                                                                | 1              | 2              | 6       | 3 |   |
| Global Operations [Member]                                                          |           |           |    |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |    |   |   |
| External sales and revenues, net                                                    | 46             | 82             | 154     | 223 |   |
| Segment Assets                                                                      | 202            |           | 202     |   | 296 |
| Intersegment sales and revenues                                                     | 1              | 8              | 12      | 27 |   |
| Sales and revenues, net                                                             | 46             | 82             | 154     | 223 |   |
| Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent        | 1              | 1              | (12)    | 10 |   |
| Income Tax Expense (Benefit)                                                        | 0              | 0              | 0       | 0 |   |
| Segment Profit Loss                                                                 | 1              | 1              | (12)    | 10 |   |
| Depreciation, Depletion and Amortization                                            | 1              | 3              | 5       | 7 |   |
| Interest expense                                                                    | 0              | 0              | 0       | 0 |   |
| Equity in income of non-consolidated affiliates                                     | 0              | 0              | 0       | (1) |   |
| Capital expenditures                                                                | 1              | 1              | 3       | 2 |   |
| Financial Services Operations                                                       |           |           |    |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |    |   |   |
| Interest Revenue (Expense), Net                                                     | 29             | 53             | 103     | 161 |   |
| External sales and revenues, net                                                    | 39             | 46             | 135     | 141 |   |
| Segment Assets                                                                      | 2,285          |           | 2,285   |   | 2,774 |
| Intersegment sales and revenues                                                     | 10             | 28             | 35      | 85 |   |
| Sales and revenues, net                                                             | 39             | 46             | 135     | 141 |   |
| Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent        | 10             | 30             | 51      | 93 |   |
| Income Tax Expense (Benefit)                                                        | 0              | 0              | 0       | 0 |   |
| Segment Profit Loss                                                                 | 10             | 30             | 51      | 93 |   |
| Depreciation, Depletion and Amortization                                            | 16             | 16             | 48      | 48 |   |
| Interest expense                                                                    | 16             | 27             | 55      | 83 |   |
| Equity in income of non-consolidated affiliates                                     | 0              | 0              | 0       | 0 |   |
| Capital expenditures                                                                | 0              | 0              | 0       | 2 |   |
| Corporate And Eliminations [Member]                                                 |           |           |    |   |   |
| **Segment Reporting Information [Line Items]**                                      |           |           |    |   |   |
| External sales and revenues, net                                                    | 0              | 3              | 2       | 9 |   |
| Segment Assets                                                                      | 1,826          |           | 1,826   |   | $ 1,454 |
| Intersegment sales and revenues                                                     | (38)           | (83)           | (84)    | (192) |   |
| Sales and revenues, net                                                             | 0              | 3              | 2       | 9 |   |
| Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent        | (123)          | (191)          | (338)   | (604) |   |
| Income Tax Expense (Benefit)                                                        | (8)            | (29)           | (10)    | (9) |   |
| Segment Profit Loss                                                                 | (115)          | (162)          | (328)   | (595) |   |
| Depreciation, Depletion and Amortization                                            | 2              | 1              | 5       | 7 |   |
| Interest expense                                                                    | 55             | 49             | 144     | 160 |   |
| Equity in income of non-consolidated affiliates                                     | 0              | 0              | 0       | 0 |   |
| Capital expenditures                                                                | $ 5            | $ 4            | $ 13    | $ 14 |   |

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Amount of profit or loss recognized by the reportable segment.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.
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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 tax of income (loss) from continuing operations attributable to the parent.
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| - Definition
Amount of income (loss) for proportionate share of equity method investee's income (loss).
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| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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| - Definition
Amount of the cost of borrowed funds accounted for as interest expense.
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| - Definition
Amount of interest revenue (income derived from investments in debt securities and on cash and cash equivalents) net of interest expense (cost of borrowed funds accounted for as interest).
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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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| - 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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