| **Segment Reporting - Summary of Segment Long Lived Assets and Revenue (Details) - USD ($) $ in Millions** | 3 Months Ended | 12 Months Ended |
|------------------------------------------------------------------------------------------------------------|----------------|-----------------|
||
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    | $ 2,063        | $ 2,086         | $ 2,197 | $ 1,765 | $ 2,488 | $ 2,538 | $ 2,693 | $ 2,421 | $ 8,111 | $ 10,140 | $ 10,806 |
| UNITED STATES                                                                                              |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Long-Lived Assets                                                                                          | 999            |            |   |   | 1,126 |   |   |   | 999 | 1,126 |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 6,186 | 7,699 | 7,760 |
| Other Countries                                                                                            |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Long-Lived Assets                                                                                          | 8              |            |   |   | 11 |   |   |   | 8 | 11 |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 506 | 631 | 807 |
| CANADA                                                                                                     |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Long-Lived Assets                                                                                          | 20             |            |   |   | 19 |   |   |   | 20 | 19 |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 604 | 774 | 749 |
| MEXICO                                                                                                     |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Long-Lived Assets                                                                                          | 202            |            |   |   | 186 |   |   |   | 202 | 186 |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 575 | 653 | 657 |
| BRAZIL                                                                                                     |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Long-Lived Assets                                                                                          | $ 103          |            |   |   | $ 98 |   |   |   | 103 | 98 |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 240 | 383 | 833 |
| Truck                                                                                                      |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 5,176 | 6,845 | 7,137 |
| Financial Services Operations                                                                              |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 136 | 145 | 153 |
| Parts                                                                                                      |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 2,216 | 2,399 | 2,424 |
| Engine                                                                                                     |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 583 | 751 | 1,092 |
| Financial Services Operations                                                                              |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Investment Income, Interest                                                                                |           |            |   |   |   |   |   |   | 167 | 175 | 170 |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 235 | 241 | $ 232 |
| Reclassification of Sales | UNITED STATES                                                                  |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   |   | (23) |   |
| Reclassification of Sales | Other Countries                                                                |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | 103 | $ 23 |   |
| Reclassification of Sales | BRAZIL                                                                         |           |            |   |   |   |   |   |   |   |   |   |
| **Revenues from External Customers and Long-Lived Assets [Line Items]**                                    |           |            |   |   |   |   |   |   |   |   |   |
| Sales and revenues, net                                                                                    |           |            |   |   |   |   |   |   | $ (103) |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.
+ References
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| - Definition
Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.
+ References
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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).
+ 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.
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No definition available.
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