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

| 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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267
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| 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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| 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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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