| **Finance Receivables - Schedule of Finance Revenues (Details) - USD ($) $ in Millions** | 3 Months Ended | 9 Months Ended |
|------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Retail notes and finance leases revenue                                                  | $ 14           | $ 16           | $ 48 | $ 45 |
| Gross finance revenues                                                                   | 49             | 74             | 170 | 226 |
| Intercompany Revenues                                                                    | 10             | 28             | 35 | 85 |
| Finance Revenues, Net                                                                    | 36             | 46             | 128 | 141 |
| Financing Receivable [Member]                                                            |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Operating lease revenue                                                                  | 20             | 19             | 64 | 62 |
| Wholesale Portfolio [Member] | Notes Receivable [Member]                                 |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Interest Income, Operating                                                               | 14             | 31             | 49 | 93 |
| Retail And Wholesale Portfolios [Member]                                                 |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Interest Income, Operating                                                               | 1              | 8              | 9 | 26 |
| Financial Services Operations                                                            |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Finance Revenues, Net                                                                    | $ 39           | $ 46           | $ 135 | $ 141 |

| X                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Finance Revenue [Line Items]
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Finance Revenues From On Balance Sheet Receivables
+ References
No definition available.
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| X                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Finance Revenues, Net
+ References
No definition available.
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| X                                                                                                                                                                                                                               |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Intercompany Revenues
+ References
No definition available.
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| X                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Retail Notes And Finance Leases Revenue
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.
+ References
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| X                                                                                                                                                                                             |
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| X                                                                                                                                                                                                  |
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| X                                                                                                                                                                                          |
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| X                                                                                                                                                                                                            |
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| X                                                                                                                                                                   |
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