| **Discontinued Operations - Narrative (Details) - USD ($) $ in Millions** | 3 Months Ended | 6 Months Ended |        |
|---------------------------------------------------------------------------|----------------|----------------|--------|
||
| **Statements of Operations for Discontinued Operations [Line Items]**     |           |           |   |   |   |   |
| Asset impairment charges                                                  | $ 3            | $ 1            |   | $ 5 | $ 8 |   |
| Impairment of Intangible Assets (Excluding Goodwill)                      |           |           |   | 5 | $ 8 |   |
| Goodwill                                                                  | $ 38           |           |   | $ 38 |   | $ 38 |
| North America Truck [Member]                                              |           |           |   |   |   |   |
| **Statements of Operations for Discontinued Operations [Line Items]**     |           |           |   |   |   |   |
| Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)    |           |           | $ 7    |   |   |   |

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| - Definition
[Line Items] for Statements of Operations for Discontinued Operations [Table]
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| - Definition
Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.
+ References
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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
The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.
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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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