| **Commitments and Contingencies - Commitments and Contingencies (Details)**                                       | 3 Months Ended | 9 Months Ended | 1 Months Ended | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended | 0 Months Ended | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |            |            |           | 3 Months Ended |           |            | 9 Months Ended |            |        |             |
|-------------------------------------------------------------------------------------------------------------------|----------------|----------------|----------------|----------------|----------------|----------------|----------------|----------------|----------------|----------------|----------------|-----------------|------------|------------|-----------|----------------|-----------|------------|----------------|------------|--------|-------------|
||
| **Loss Contingencies [Line Items]**                                                                               |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Operating Agreement Excess Loss Percentage                                                                        |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        | 10.00% |   |   |   |   |   |   |   |
| Loss Sharing Agreement, Percentage                                                                                |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        | 9.50% |   |   |   |   |   |   |   |
| Off Balance Sheet Finance Receivables                                                                             |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   | $ 1,400,000,000 |   |   |   |   |   |
| Off Balance Sheet Finance Receivables Related Originations                                                        |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   | 2,200,000,000 | 2,000,000,000 |   |   |   |   |   |
| Payments to Acquire Equipment on Lease                                                                            |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   | 164,000,000 |   |   |
| Long-term Debt                                                                                                    |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   | 218,000,000 | 195,000,000 |
| 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                                                             |           | 108,000,000    |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Line of Credit Facility, Current Borrowing Capacity                                                               |           | 13,000,000     |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Line of Credit Facility, Remaining Borrowing Capacity                                                             |           | 9,000,000      |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Purchase commitments                                                                                              |           | 168,000,000    |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Long Term Purchase Commitment Cancellation Fees                                                                   |           | 36,000,000     |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Number of Contaminated Sites                                                                                      |           | 2              |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Number of Contaminated Sites in Sao Paulo, Brazil                                                                 |           | 2              |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Accrual for environmental loss contingencies                                                                      |           | 22,000,000     |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Damages sought, value                                                                                             |           |           | 3,000,000      | 1,300,000      |           |           |           |           | 50,000,000     | 1,000,000      | 2,000,000      | 10,850,000      | 25,000,000 | 22,000,000 |      |           | 3,800,000 | 42,000,000 |           |       |   |        |   |   |   |   |   |   |   |   |
| Loss Contingency, Loss in Period                                                                                  |           |           |           |           |           |           |           |           |           |           |           |            |       |       | 8,500,000 | 20,000,000     | 9,000,000 |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Estimate of possible loss                                                                                         |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      | 16,000,000 | 74,000,000     | 70,000,000 |   |        |   |   |   |   |   |   |   |   |
| Proceeds from Legal Settlements                                                                                   | 35,000,000     |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       |   |        |   |   |   |   |   |   |   |   |
| Notice of Violation, number                                                                                       |           |           |           |           |           |           |           |           |           |           |           |            |       |       |      |           |      |       |           |       | 7,600  |        |   |   |   |   |   |   |   |   |
| Regulatory Penalty                                                                                                |           |           |           |           | $ 1,000,000    | $ 7,000,000    | $ 2,000,000    | $ 29,000,000   |           |           |           |            |       |       |      |           |      |       |           |       |   | $ 2,500,000 |   |   |   |   |   |   |   |   |

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Operating Agreement Excess Loss Percentage
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| - Definition
Total costs accrued as of the balance sheet date for environmental loss contingencies.
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.
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| - Definition
Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.
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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).
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| - Definition
Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
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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
Cash received for the settlement of litigation during the current period.
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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.
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