| **Commitments and Contingencies - Commitments and Contingencies (Details)**                                       | 3 Months Ended | 12 Months Ended | 0 Months Ended | 1 Months Ended | 12 Months Ended |              |            |           | 12 Months Ended | 3 Months Ended | 6 Months Ended |            |            | 6 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                                                                        |           |            |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        | 10.00% |            |   |   |   |   |   |   |   |   |   |   |
| Off Balance Sheet Finance Receivables                                                                             |           |            |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   | $ 1,400,000,000 | $ 1,200,000,000 |   |   |   |   |   |   |   |   |   |
| Off Balance Sheet Finance Receivables Related Originations                                                        |           |            |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   | 2,000,000,000   | 1,600,000,000 |   |   |   |   |   |   |   |   |   |
| Payments to Acquire Equipment on Lease                                                                            |           | 432,000,000     | 61,000,000     | 71,000,000     |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   | 197,000,000 |   |   |   |   |   |   |
| Long-term Debt                                                                                                    |           | 5,085,000,000   |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   | 3,219,000,000 | 2,905,000,000 | 218,000,000 | 0 | 219,000,000 | 167,000,000 |
| 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                                                             |           | 115,000,000     |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Line of Credit Facility, Remaining Borrowing Capacity                                                             |           | 7,000,000       |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Purchase commitments                                                                                              |           | 370,000,000     |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Long Term Purchase Commitment Cancellation Fees                                                                   |           | 51,000,000      |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Number of Contaminated Sites                                                                                      |           | 2               |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Number of Contaminated Sites in Sao Paulo, Brazil                                                                 |           | 2               |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Accrual for environmental loss contingencies                                                                      |           | 21,000,000      |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Damages sought, value                                                                                             |           |            |           |           |            |         | 50,000,000 | 1,000,000 | 2,000,000       | 10,850,000     | 25,000,000     | 22,000,000 | 12,000,000 | 42,000,000     |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |
| Potential patent infringement, number of patents                                                                  |           |            |           |           |            |         |       |      |            |           |           |       |       |           |            |       |   | 3      |        |   |            |   |   |   |   |   |   |   |   |   |   |
| 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                                                                                                |           |            |           |           | $ 36,000,000    | $ 34,000,000 |       |      |            |           |           |       |       |           |            |       |   |   | $ 2,500,000 |   |            |   |   |   |   |   |   |   |   |   |   |
| Maximum Non-Conformance Penalty per unit                                                                          |           | 4,287           | 3,775          |           |            |         |       |      |            |           |           |       |       |           |            |       |   |   |        |   |            |   |   |   |   |   |   |   |   |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Historic Losses On Finance Receivables Measured As Percentage Of Average Balance Of Related Finance Receivable
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Length of Agreement
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Length of Potential Automatic Extension Years
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| X                                                                                                                                                                                                                                                                              |
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| - Definition
Long Term Purchase Commitment Cancellation Fees
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| - Definition
Loss Contingency, Potential Patent Infringement, Number of Patents
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Maximum Non-Conformance Penalty Per Unit1
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Notice of Violation, number of engines
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| - Definition
Number of Contaminated Sites
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Number of Contaminated Sites in Sao Paulo, Brazil
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| X                                                                                                                                                                                                                                                           |
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| - Definition
Off Balance Sheet Finance Receivables1
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| - Definition
Off Balance Sheet Finance Receivables Related Originations1
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| - Definition
Operating Agreement Excess Loss Percentage
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Regulatory Penalty
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total costs accrued as of the balance sheet date for environmental loss contingencies.
+ References
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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
Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).
+ References
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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 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 cash outflow for payments to acquire rented equipment which is recorded as an asset.
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| - Definition
Cash received for the settlement of litigation during the current period.
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