| **Finance Receivables (Details) (USD $)**                                                                                                                                                                                                        | 12 Months Ended |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                 |            |  |   |  |   |
| Loans and Leases Receivable, Net Amount                                                                                                                                                                                                          | $ 2,100,000,000 |  | $ 2,900,000,000 |  |   |
| Financing Receivable By Class Number of Portfolio Segments                                                                                                                                                                                       | 2               |  |   |  |   |
| Loans and Leases Receivable, Gross, Carrying Amount, Covered                                                                                                                                                                                     | 2,176,000,000   |  | 2,947,000,000 |  |   |
| Less: Allowance for Doubtful accounts                                                                                                                                                                                                            | 27,000,000      |  | 34,000,000 |  |   |
| Total finance receivables, net                                                                                                                                                                                                                   | 2,149,000,000   |  | 2,913,000,000 |  |   |
| Finance Receivables, Current                                                                                                                                                                                                                     | 1,663,000,000   | [1] | 2,198,000,000 | [1] |   |
| Noncurrent portion, net                                                                                                                                                                                                                          | 486,000,000     |  | 715,000,000 |  |   |
| Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale, Gain (Loss) on Sale                                                                                                               | 4,600,000,000   |  | 4,500,000,000 |  | 1,500,000,000 |
| Retail Portfolio [Member]                                                                                                                                                                                                                        |            |  |   |  |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                 |            |  |   |  |   |
| Loans and Leases Receivable, Gross, Carrying Amount, Covered                                                                                                                                                                                     | 1,048,000,000   |  | 1,613,000,000 |  |   |
| Wholesale Portfolio [Member]                                                                                                                                                                                                                     |            |  |   |  |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                 |            |  |   |  |   |
| Loans and Leases Receivable, Gross, Carrying Amount, Covered                                                                                                                                                                                     | 1,128,000,000   |  | 1,334,000,000 |  |   |
| Financial Services Operations [Member]                                                                                                                                                                                                           |            |  |   |  |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                 |            |  |   |  |   |
| Assets Net Of Intercompany Balances                                                                                                                                                                                                              | $ 2,600,000,000 |  | $ 3,500,000,000 |  |   |
|                                                                                                                                                                                                                                                  |
| [1]The current portion of finance receivables is computed based on contractual maturities. Actual cash collections typically vary from the contractual cash flows because of prepayments, extensions, delinquencies, credit losses, and renewals |

| X                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Assets Net Of Intercompany Balances
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reflects carrying amount of all categories of loans and leases held in portfolio, net of unearned income and the allowance for losses on loans and leases, due from customers, clients, lessees, borrowers, or others more than one year from the balance sheet date (or the normal operating cycle, whichever is longer).
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| X                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing Receivable By Class Number of Portfolio Segments
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing receivables that are current.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate gross carrying amount of loans and leases receivable covered by loss sharing agreements.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reflects, by transferred financial asset type, the amount of sales proceeds in excess of or deficient from the sum of the carrying amounts of transferred financial assets plus transaction costs, including those transactions in which the seller/transferor has continuing involvement with the financial assets that have been transferred.
+ References
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