| **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                                                  | $ 9            | $ 12           | $ 28 | $ 37 |
| Gross finance revenues                                                                   | 60             | 63             | 177 | 183 |
| Less: Intercompany revenues                                                              | (26)           | (26)           | (75) | (75) |
| Finance revenues                                                                         | 34             | 37             | 102 | 108 |
| Financing Receivable [Member]                                                            |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Operating lease revenue                                                                  | 17             | 16             | 49 | 46 |
| Wholesale Portfolio [Member] | Notes Receivable [Member]                                 |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Interest Income, Operating                                                               | 29             | 27             | 81 | 75 |
| Retail And Wholesale Portfolios [Member]                                                 |           |           |   |   |
| **Finance Revenues [Line Items]**                                                        |           |           |   |   |
| Interest Income, Operating                                                               | $ 5            | $ 8            | $ 19 | $ 25 |

| 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
Retail Notes And Finance Leases Revenue
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate financial services revenue and operating interest income earned during the reporting period.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(d)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688
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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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688
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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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39896-112707
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.
+ 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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