| **Summary of Significant Accounting Policies - Product Warranty Liability (Details) - USD ($) $ in Millions**      | 12 Months Ended |        |        |
|--------------------------------------------------------------------------------------------------------------------|-----------------|--------|--------|
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| **Product Liability Contingency [Line Items]**                                                                     |            |   |   |   |   |
| Extended Product Warranty Accrual                                                                                  |            |   |   | $ 14 |   |
| Document Type                                                                                                      | 10-K            |   |   |   |   |
| Product Warranty Accrual                                                                                           | $ 449           | $ 510  | $ 529  |   | $ 629 |
| Product Warranty Accrual, Warranties Issued                                                                        | 162             | 249    | 211    |   |   |
| Product Warranty Accrual, Currency Translation, Increase (Decrease)                                                |            |   | 1      |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:** |            |   |   |   |   |
| Adjustments to pre-existing warranties(A)(B)                                                                       | 40              | 3      | (9)    |   |   |
| **Extended Warranty Program:**                                                                                     |            |   |   |   |   |
| Product Warranty Accrual, Payments                                                                                 | (263)           | (283)  | (303)  |   |   |
| standard and extended product warranty other adjustments                                                           | 0               | 12     |   |   |   |
| Product Warranty Accrual, Current                                                                                  | 209             | 233    | 255    |   |   |
| Product Warranty Accrual, Noncurrent                                                                               | 240             | 277    | 274    |   |   |
| North America Truck [Member]                                                                                       |            |   |   |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:** |            |   |   |   |   |
| Product Warranty Expense                                                                                           |            | 14     | 29     |   |   |
| Field Campaign to address issues in products sold [Member] | North America Truck [Member]                          |            |   |   |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:** |            |   |   |   |   |
| Product Warranty Expense                                                                                           | $ 23            | 27     | 10     |   |   |
| Pre-existing Warranty [Member] | North America Truck [Member]                                                      |            |   |   |   |   |
| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:** |            |   |   |   |   |
| Product Warranty Expense                                                                                           |            | $ 13   | $ 33   |   |   |
| Minimum                                                                                                            |            |   |   |   |   |
| **Product Liability Contingency [Line Items]**                                                                     |            |   |   |   |   |
| Product Warranty Coverage Period                                                                                   | 1 year          |   |   |   |   |
| Maximum                                                                                                            |            |   |   |   |   |
| **Product Liability Contingency [Line Items]**                                                                     |            |   |   |   |   |
| Product Warranty Coverage Period                                                                                   | 5 years         |   |   |   |   |
| Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations [Member]                         |            |   |   |   |   |
| **Product Liability Contingency [Line Items]**                                                                     |            |   |   |   |   |
| Extended Product Warranty Accrual                                                                                  |            |   |   | $ 2 |   |

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Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard product warranty liability.
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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.
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| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).
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| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.
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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.
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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.
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Amount of increase in the standard and extended product warranty accrual from warranties issued.
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| - Definition
The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.
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| - Definition
Amount of foreign currency translation gain (loss) which decreases (increases) the standard and extended product warranty accrual.
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