| **Allowance for Doubtful Accounts - Schedule of Allowance for Retail, Wholesale, Trade & Other (Details) - USD ($) $ in Millions** | 12 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Allowance for doubtful accounts at beginning of period                                                                                 | $ 44            | $ 50 | $ 48 |
| Provision for doubtful accounts, net of recoveries                                                                                     | 16              | 4 | 10 |
| Charge-off of accounts                                                                                                                 | (11)            | (12) | (8) |
| Financing Receivable, Allowance for Credit Losses, Other                                                                               | (6)             |   | (3) |
| Allowance for doubtful accounts at end of period                                                                                       | 44              | 44 | 50 |
| SEC Schedule, 12-09, Allowance, Credit Loss [Member]                                                                                   |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Accounts Receivable, Allowance for Credit Loss, Recovery                                                                               | 1               | 2 | 3 |
| Retail Portfolio [Member]                                                                                                              |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Allowance for doubtful accounts at beginning of period                                                                                 | 20              | 19 | 17 |
| Provision for doubtful accounts, net of recoveries                                                                                     | 12              | 5 | 7 |
| Charge-off of accounts                                                                                                                 | (9)             | (6) | (7) |
| Financing Receivable, Allowance for Credit Losses, Other                                                                               | (1)             |   | (1) |
| Allowance for doubtful accounts at end of period                                                                                       | 23              | 20 | 19 |
| Impaired Financing Receivable, Average Recorded Investment                                                                             | 29              | 21 |   |
| Wholesale Portfolio [Member]                                                                                                           |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Allowance for doubtful accounts at beginning of period                                                                                 | 3               | 3 | 3 |
| Provision for doubtful accounts, net of recoveries                                                                                     | (1)             | 0 | 0 |
| Charge-off of accounts                                                                                                                 | 0               | 0 | 0 |
| Financing Receivable, Allowance for Credit Losses, Other                                                                               | 0               |   | 0 |
| Allowance for doubtful accounts at end of period                                                                                       | 2               | 3 | 3 |
| Trade and Other Receivables [Member]                                                                                                   |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Allowance for doubtful accounts at beginning of period                                                                                 | 21              | 28 | 28 |
| Provision for doubtful accounts, net of recoveries                                                                                     | 5               | (1) | 3 |
| Charge-off of accounts                                                                                                                 | (2)             | (6) | (1) |
| Financing Receivable, Allowance for Credit Losses, Other                                                                               | (5)             |   | (2) |
| Allowance for doubtful accounts at end of period                                                                                       | 19              | 21 | 28 |
| Trade and Other Receivables [Member]                                                                                                   |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Accounts Receivable, Allowance for Credit Loss, Recovery                                                                               | 0               | 0 | 0 |
| Wholesale Portfolio [Member]                                                                                                           |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Accounts Receivable, Allowance for Credit Loss, Recovery                                                                               | 0               | 0 | 0 |
| Retail Portfolio [Member]                                                                                                              |            |   |   |
| **Accounts Receivable, Allowance for Credit Loss [Roll Forward]**                                                                      |            |   |   |
| Accounts Receivable, Allowance for Credit Loss, Recovery                                                                               | $ 1             | $ 2 | $ 3 |

| X                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable, Allowance for Credit Losses, Other
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase in allowance for credit loss on accounts receivable, from recovery.
+ References
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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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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of writeoff of financing receivable, charged against allowance for credit loss.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.
+ References
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| X                                                                                                                                                                         |
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| X                                                                                                                                                                   |
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| X                                                                                                                                                                |
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