| **Commitments and Contingencies (Details)In Millions, unless otherwise specified**                                | 12 Months Ended | 0 Months Ended | 12 Months Ended |        |        |        | 12 Months Ended |        | 12 Months Ended |
|-------------------------------------------------------------------------------------------------------------------|-----------------|----------------|-----------------|--------|--------|--------|-----------------|--------|-----------------|
||
| **Loss Contingencies [Line Items]**                                                                               |            |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Length of Agreement                                                                                               |            |           |            |   |   |   |            |   |            |   |   |   |   | 3 years |   |   |   |
| Length Of Potential Automatic Extension Years                                                                     |            |           |            |   |   |   |            |   |            |   |   |   |   | 1 year |   |   |   |
| Operating Agreement Excess Loss Percentage                                                                        |            |           |            |   |   |   |            |   |            |   |   |   |   | excess of the first 10% |   |   |   |
| Loss Sharing Arrangement Reimbursement For Credit Losses In Excess Of Original Value Of Financed Contract Percent | 10.00%          |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Outstanding finance receivables, off-balance sheet                                                                |            |           |            |   |   |   |            |   |            |   |   |   |   | $ 723 | $ 144 |   |   |
| Related originations of outstanding finance receivables, off-balance sheet                                        |            |           |            |   |   |   |            |   |            |   |   |   |   | 818 | 159 |   |   |
| Historical losses on finance receivables, measured as percentage of average balance of related finance receivable |            |           |            |   |   |   |            |   |            |   |   |   |   |   |   | 0.30% | 2.10% |
| Available stand-by letters of credit and surety bonds                                                             | 61              |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Unused credit commitments outstanding                                                                             | 30              |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Purchase commitments                                                                                              | 117             |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Cancellation fees                                                                                                 | 32              |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Accrual for environmental loss contingencies                                                                      | 21              |           |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Defendent, number of former executive officers                                                                    |            | 2              | 2               |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Defendant, number of executive officers                                                                           |            | 1              | 1               |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Payment for legal settlement                                                                                      |            | 13             |            |   |   |   |            |   |            |   |   |   |   |   |   |   |   |
| Damages sought, value                                                                                             |            |           |            | 1.20   | 2.00   |   | 6.40            | 10.85  | 42.00           |   |   |   |   |   |   |   |   |
| Estimate of possible loss                                                                                         |            |           |            |   |   |   |            |   | 16.0            | $ 43.8 | 74.0 | 70.0 |   |   |   |   |   |
| Number of substantially similiar lawsuits filed                                                                   |            |           |            |   |   | 19     |            |   |            |   |   |   |   |   |   |   |   |
| Potential patent infringement, number of patents                                                                  |            |           |            |   |   |   |            |   |            |   |   |   | 3 |   |   |   |   |

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Cancellation Fees
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| - Definition
Historic Losses On Finance Receivables Measured As Percentage Of Average Balance Of Related Finance Receivable
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| X                                                                                                                                                                                                                               |
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Length of Agreement
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Length Of Potential Automatic Extension Years
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Loss Contingency Defendent Number Of Executive Officers
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Loss Contingency Defendent Number Of Former Executive Officers
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Loss Contingency, Potential Patent Infringement, Number of Patents
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| - Definition
Loss Sharing Arrangement Reimbursement For Credit Losses In Excess Of Original Value Of Financed Contract Percent
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| X                                                                                                                                                                                                                                                                     |
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Off Balance Sheet Risks Finance Receivables
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Off Balance Sheet Risks Finance Receivables Related Originations
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Operating Agreement Excess Loss Percentage
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Unused Credit Commitments Outstanding
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total costs accrued as of the balance sheet date for environmental loss contingencies.
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| - Definition
The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.
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| - Definition
The minimum amount the entity agreed to spend under the long-term purchase commitment.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The value (monetary amount) of the award the plaintiff seeks in the legal matter.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.
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| - Definition
The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.
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| - Definition
The total number of new claims filed pertaining to a loss contingency during the period.
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