| **Goodwill and Other Intangible assets, Net Carrying Amount of Goodwill for Each Operating Segment (Details) - USD ($) $ in Millions** | 3 Months Ended | 12 Months Ended |        |
|----------------------------------------------------------------------------------------------------------------------------------------|----------------|-----------------|--------|
||
| **Goodwill [Line Items]**                                                                                                              |           |            |   |   |   |   |
| Goodwill                                                                                                                               | $ 184          |            | $ 38   | $ 38 | $ 184 | $ 280 |
| Goodwill, Impairment Loss                                                                                                              |           |            | 0      | (142) | (81) |   |
| Goodwill, Translation Adjustments                                                                                                      |           |            |   | (4) | (12) |   |
| Goodwill, Subsequent Recognition of Deferred Tax Asset                                                                                 |           |            |   |   | (3) |   |
| North America Truck [Member]                                                                                                           |           |            |   |   |   |   |
| **Goodwill [Line Items]**                                                                                                              |           |            |   |   |   |   |
| Goodwill                                                                                                                               | 0              |            | 0      | 0 | 0 | 82 |
| Goodwill, Impairment Loss                                                                                                              | (77)           | $ (4)           | 0      | 0 | (81) |   |
| Goodwill, Translation Adjustments                                                                                                      |           |            |   | 0 | 0 |   |
| Goodwill, Subsequent Recognition of Deferred Tax Asset                                                                                 |           |            |   |   | (1) |   |
| North America Parts [Member]                                                                                                           |           |            |   |   |   |   |
| **Goodwill [Line Items]**                                                                                                              |           |            |   |   |   |   |
| Goodwill                                                                                                                               | 38             |            | 38     | 38 | 38 | 38 |
| Goodwill, Impairment Loss                                                                                                              |           |            | 0      | 0 | 0 |   |
| Goodwill, Translation Adjustments                                                                                                      |           |            |   | 0 | 0 |   |
| Goodwill, Subsequent Recognition of Deferred Tax Asset                                                                                 |           |            |   |   | 0 |   |
| Global Operations [Member]                                                                                                             |           |            |   |   |   |   |
| **Goodwill [Line Items]**                                                                                                              |           |            |   |   |   |   |
| Goodwill                                                                                                                               | $ 146          |            | 0      | 0 | 146 | $ 160 |
| Goodwill, Impairment Loss                                                                                                              |           |            | $ 0    | (142) | 0 |   |
| Goodwill, Translation Adjustments                                                                                                      |           |            |   | $ (4) | (12) |   |
| Goodwill, Subsequent Recognition of Deferred Tax Asset                                                                                 |           |            |   |   | $ (2) |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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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.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of (increase) decrease to an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from the subsequent recognition of deferred tax assets.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
+ References
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| X                                                                                                                                                         |
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| X                                                                                                                                                        |
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