| **Finance Receivables Finance Revenues (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended |
|---------------------------------------------------------------------------------------------------|-----------------|
||
| **Finance revenues from on-balance sheet receivables:**                                           |            |   |   |
| Retail notes and finance leases revenue                                                           | $ 136           | $ 183 |   |
| Operating lease revenue                                                                           | 32              | 33 |   |
| Total finance revenues from on-balance sheet receivables                                          | 288             | 273 |   |
| **Revenues from off-balance sheet securitization:**                                               |            |   |   |
| Gross finance revenues                                                                            | 290             | 309 |   |
| Less: Intercompany revenues                                                                       | 90              | 90 |   |
| Finance revenues                                                                                  | 200             | 219 | 269 |
| Off Balance Sheet Securitization Transactions [Member]                                            |            |   |   |
| **Revenues from off-balance sheet securitization:**                                               |            |   |   |
| Fair value adjustment                                                                             | 1               | 37 |   |
| Excess spread income                                                                              | 0               | 32 |   |
| Fees and Commissions                                                                              | 0               | 6 |   |
| Gain (loss) on sale of finance receivables                                                        | 1               | (39) |   |
| Securitization income                                                                             | 2               | 36 |   |
| **Cash flows from off-balance sheet securitization transactions:**                                |            |   |   |
| Proceeds from sales of finance receivables                                                        |            | 3,509 | 4,178 |
| Servicing fees                                                                                    |            | 6 | 8 |
| Cash from net excess spread                                                                       |            | 32 | 31 |
| Cash Flows Between Transferor and Transferee Investment Income                                    |            | 0 | 1 |
| Net cash from securitization transactions                                                         |            | 3,547 | 4,218 |
| Wholesale Portfolio [Member] | Notes Receivable [Member]                                          |            |   |   |
| **Finance revenues from on-balance sheet receivables:**                                           |            |   |   |
| Finance revenues interest income                                                                  | 93              | 39 |   |
| Retail And Wholesale Portfolios [Member] | Accounts Receivable [Member]                           |            |   |   |
| **Finance revenues from on-balance sheet receivables:**                                           |            |   |   |
| Finance revenues interest income                                                                  | $ 27            | $ 18 |   |

| X                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Cash Flows Between Transferee And Transferor Cash From Net Excess Spread
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Cash Flows Between Transferor And Transferee Net Cash From Securitization Transactions
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| X                                                                                                                                                                                                                                                            |
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Finance Revenues Excess Spread Income
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| X                                                                                                                                                                                                                                                                                    |
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Finance Revenues From On Balance Sheet Receivables
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Gross Finance Revenues
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| X                                                                                                                                                                                                                                                               |
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Retail Notes And Finance Leases Revenue
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| X                                                                                                                                                                                                                                                                                                                      |
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Revenue From Off Balance Sheet Securitization Fair Value Adjustments
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Securitization Income
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Cash Flows between a transferee and a transferor attributable to servicing fees related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total fees and commissions earned from providing services such as leasing of space or maintaining: (1) depositor accounts; (2) transfer agent; (3) fiduciary and trust; (4) brokerage and underwriting; (5) mortgage; (6) credit cards; (7) correspondent clearing; and (8) other such services and activities performed for others.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate financial services revenue and operating interest income earned during the reporting period.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The net gain (loss) resulting from the sale, transfer, termination, or other disposition of assets during the period, excluding transactions involving capital leases, assets-held- or available-for-lease, and other real estate owned which, to the extent appropriate, are included in gains (losses) on the disposition of assets in nonoperating income (expense).
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Interest generated from day to day operating activities of the business.  This element represents a revenue generating activity and is therefore gross (before any related cost of revenue items).
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Revenues arising 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, such as 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.
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