| **Debt - Narrative (Details)**                                                                                                                             | 1 Months Ended | 3 Months Ended | 6 Months Ended |                 |                 |               |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|----------------|-----------------|-----------------|---------------|
||
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Line of Credit Facility, Maximum Borrowing Capacity                                                                                                        |           |           |           | $ 100,000,000   | $ 100,000,000   |          |   |   |   |
| Payments of Debt Issuance Costs                                                                                                                            |           |           |           |            | 1,000,000       | $ 7,000,000   |   |   |   |
| Cash Dividends Paid to Parent Company by Consolidated Subsidiaries                                                                                         |           | $ 30,000,000   |           |            |            |          |   |   |   |
| Proceeds from issuance of securitized debt                                                                                                                 |           |           |           |            | 75,000,000      | $ 250,000,000 |   |   |   |
| Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]                                                                              |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Option Indexed to Issuer's Equity, Strike Price | $ / shares                                                                                               |           |           |           | $ 54.07         |            |          |   |   |   |
| Debt Instrument, Convertible, Conversion Ratio                                                                                                             |           |           |           | 18.4946         |            |          |   |   |   |
| Financial Services Operations [Member] | VFN Facility [Member]                                                                                             |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Face Amount                                                                                                                               |           |           |           | $ 375,000,000   | 375,000,000     |          |   | $ 500,000,000 |   |
| Financial Services Operations [Member] | Line of Credit [Member]                                                                                           |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Long-term Debt                                                                                                                                             |           |           |           | 947,000,000     | 947,000,000     |          |   |   | $ 1,063,000,000 |
| Manufacturing Operations [Member] | Line of Credit [Member]                                                                                                |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Unamortized Discount                                                                                                                      |           |           |           | 15,000,000      | 15,000,000      |          |   |   | 17,000,000 |
| Long-term Debt                                                                                                                                             |           |           |           | $ 1,022,000,000 | $ 1,022,000,000 |          |   |   | 1,023,000,000 |
| Manufacturing Operations [Member] | Convertible Subordinated Debt [Member] | Four Point Five Zero Senior Subordinated Convertible Notes [Member]           |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Interest Rate, Stated Percentage                                                                                                          |           |           |           | 4.50%           | 4.50%           |          |   |   |   |
| Debt Instrument, Unamortized Discount                                                                                                                      |           |           |           | $ 12,000,000    | $ 12,000,000    |          |   |   | 14,000,000 |
| Long-term Debt                                                                                                                                             |           |           |           | $ 188,000,000   | $ 188,000,000   |          |   |   | 186,000,000 |
| Manufacturing Operations [Member] | Convertible Subordinated Debt [Member] | Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member] |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Interest Rate, Stated Percentage                                                                                                          |           |           |           | 4.75%           | 4.75%           |          |   |   |   |
| Debt Instrument, Unamortized Discount                                                                                                                      |           |           |           | $ 28,000,000    | $ 28,000,000    |          |   |   | 32,000,000 |
| Long-term Debt                                                                                                                                             |           |           |           | 383,000,000     | 383,000,000     |          |   |   | 379,000,000 |
| Manufacturing Operations [Member] | Debt Of Majority Owned Dealerships [Member]                                                                            |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Long-term Debt                                                                                                                                             |           |           |           | 13,000,000      | 13,000,000      |          |   |   | 28,000,000 |
| Manufacturing Operations [Member] | Notes Payable, Other Payables [Member]                                                                                 |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Long-term Debt                                                                                                                                             |           |           |           | $ 16,000,000    | $ 16,000,000    |          |   |   | 15,000,000 |
| Manufacturing Operations [Member] | Tax Exempt Bond [Member]                                                                                               |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Interest Rate, Stated Percentage                                                                                                          |           |           |           | 6.50%           | 6.50%           |          |   |   |   |
| Long-term Debt                                                                                                                                             |           |           |           | $ 225,000,000   | $ 225,000,000   |          |   |   | 225,000,000 |
| Manufacturing Operations [Member] | Financed lease obligations [Member]                                                                                    |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Long-term Debt                                                                                                                                             |           |           |           | $ 75,000,000    | 75,000,000      |          |   |   | $ 111,000,000 |
| Convertible Debt Securities [Member] | Four Point Five Zero Senior Subordinated Convertible Notes [Member]                                                 |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Convertible, Conversion Ratio                                                                                                             |           |           |           | 17.1233         |            |          |   |   |   |
| Debt Instrument Convertible Conversion Ratio Basis                                                                                                         |           |           |           | $ 1,000         |            |          |   |   |   |
| Convertible Debt Securities [Member] | Four Point Seven Five Senior Subordinated Convertible Notes [Member] [Member]                                       |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument Convertible Conversion Ratio Basis                                                                                                         |           |           |           | 1,000           |            |          |   |   |   |
| G E Operating Agreement [Member] | Manufacturing Operations [Member] | Financed lease obligations [Member]                                                 |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Long-term Debt                                                                                                                                             |           |           |           | $ 75,000,000    | $ 75,000,000    |          |   |   |   |
| Revolving Credit Facility [Member] | Financial Services Operations [Member] | Bank Facility [Member]                                                       |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Line of Credit Facility, Maximum Borrowing Capacity                                                                                                        |           |           | $ 500,000,000  |            |            |          |   |   |   |
| Term Loan [Member] | Financial Services Operations [Member] | Bank Facility [Member]                                                                       |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Line of Credit Facility, Maximum Borrowing Capacity                                                                                                        |           |           | 229,000,000    |            |            |          |   |   |   |
| Installment Payments Set Two [Member] | Term Loan [Member] | Financial Services Operations [Member] | Bank Facility [Member]                               |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Periodic Payment, Principal                                                                                                               |           |           | $ 9,000,000    |            |            |          |   |   |   |
| Subsequent Event [Member] | Revolving Credit Facility [Member] | Financial Services Operations [Member] | Bank Facility [Member]                           |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Line of Credit Facility, Maximum Borrowing Capacity                                                                                                        |           |           |           |            |            |          | $ 400,000,000 |   |   |
| Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option                                                                               |           |           |           |            |            |          | $ 700,000,000 |   |   |
| Scenario, Forecast [Member] | Revolving Credit Facility [Member] | Financial Services Operations [Member] | Bank Facility [Member]                         |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Line of Credit Facility, Maximum Borrowing Capacity                                                                                                        | $ 275,000,000  |           |           |            |            |          |   |   |   |
| Scenario, Forecast [Member] | Term Loan [Member] | Financial Services Operations [Member] | Bank Facility [Member]                                         |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Line of Credit Facility, Maximum Borrowing Capacity                                                                                                        | 82,000,000     |           |           |            |            |          |   |   |   |
| Scenario, Forecast [Member] | Installment Payments Set Two [Member] | Term Loan [Member] | Financial Services Operations [Member] | Bank Facility [Member] |           |           |           |            |            |          |   |   |   |
| **Debt Instrument [Line Items]**                                                                                                                           |           |           |           |            |            |          |   |   |   |
| Debt Instrument, Periodic Payment, Principal                                                                                                               | $ 2,000,000    |           |           |            |            |          |   |   |   |

| X                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Debt Instrument Convertible Conversion Ratio Basis
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| - Definition
Line of Credit Facility, Accordion Feature, Higher Borrowing Capacity Option
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No definition available.
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| - Definition
This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Face (par) amount of debt instrument at time of issuance.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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No definition available.
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| - Definition
Amount of the required periodic payments applied to principal.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after accumulated amortization, of debt discount.
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| - Definition
Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
+ References
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| - Definition
Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.
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| - Definition
The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.
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| - Definition
The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.
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| X                                                                                                                                                    |
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