| **Fair Value Measurements (Level 3 Reconciliation) (Details) (USD $)In Millions, unless otherwise specified**                                                 | 3 Months Ended | 6 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| Guarantees [Member]                                                                                                                                           |           |                |   |  |   |  |   |  |
| **Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]**                                               |           |                |   |  |   |  |   |  |
| Balance at beginning of period                                                                                                                                | $ 7            |                | $ 0 |  | $ 6 |  | $ 0 |  |
| Total gains (losses) (realized/unrealized) included in earnings                                                                                               | 0              | [1]            | 0 | [1] | 0 | [1] | 0 | [1] |
| Transfers Into Level 3                                                                                                                                        |           |                |   |  | 0 |  | 0 |  |
| Transfers out of Level 3                                                                                                                                      |           |                |   |  | 0 |  | 0 |  |
| Issuance                                                                                                                                                      |           |                |   |  | 1 |  | 0 |  |
| Settlements                                                                                                                                                   | 0              |                | 0 |  | 0 |  | 0 |  |
| Balance at end of period                                                                                                                                      | 7              |                | 0 |  | 7 |  | 0 |  |
| Fair Value Change in Unrealized Gains on Assets and Liabilities Still Held                                                                                    | 0              |                | 0 |  | 0 |  | 0 |  |
| Retained Interest [Member]                                                                                                                                    |           |                |   |  |   |  |   |  |
| **Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]**                                               |           |                |   |  |   |  |   |  |
| Balance at beginning of period                                                                                                                                | 0              |                | 0 |  | 0 |  | 53 |  |
| Total gains (losses) (realized/unrealized) included in earnings                                                                                               | 0              | [1]            | 0 | [1] | 0 | [1] | 1 | [1] |
| Transfers Into Level 3                                                                                                                                        |           |                |   |  | 0 |  | 0 |  |
| Transfers out of Level 3                                                                                                                                      |           |                |   |  | 0 |  | 0 |  |
| Issuance                                                                                                                                                      |           |                |   |  | 0 |  | 0 |  |
| Settlements                                                                                                                                                   | 0              |                | 0 |  | 0 |  | (54) |  |
| Balance at end of period                                                                                                                                      | 0              |                | 0 |  | 0 |  | 0 |  |
| Fair Value Change in Unrealized Gains on Assets and Liabilities Still Held                                                                                    | 0              |                | 0 |  | 0 |  | 0 |  |
| Commodity Contract [Member]                                                                                                                                   |           |                |   |  |   |  |   |  |
| **Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]**                                               |           |                |   |  |   |  |   |  |
| Balance at beginning of period                                                                                                                                | 0              |                | 5 |  | (2) |  | 2 |  |
| Total gains (losses) (realized/unrealized) included in earnings                                                                                               | 0              | [1]            | 2 | [1] | (1) | [1] | 6 | [1] |
| Transfers Into Level 3                                                                                                                                        |           |                |   |  | 0 |  | 0 |  |
| Transfers out of Level 3                                                                                                                                      |           |                |   |  | 2 |  | 0 |  |
| Issuance                                                                                                                                                      |           |                |   |  | 0 |  | 0 |  |
| Settlements                                                                                                                                                   | 0              |                | (1) |  | 1 |  | (2) |  |
| Balance at end of period                                                                                                                                      | 0              |                | 6 |  | 0 |  | 6 |  |
| Fair Value Change in Unrealized Gains on Assets and Liabilities Still Held                                                                                    | $ 0            |                | $ 0 |  | $ 0 |  | $ 3 |  |
|                                                                                                                                                               |
| [1]For commodity contracts, gains (losses) are included in Costs of products sold. For retained interests, gains recognized are included in Finance revenues. |

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| - Definition
Transfers into liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.
+ References
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| - Definition
Transfers out of liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy that have taken place during the period.
+ References
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| - Definition
Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.
+ References
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