| **Summary of Significant Accounting Policies - Narrative (Details) (USD $)In Millions, except Per Share data, unless otherwise specified** | 12 Months Ended |
|--------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
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| **Accounting Policies [Line Items]**                                                                                                       |            |   |   |
| Number Of Segments                                                                                                                         | 4               |   |   |
| Number of Dealcors                                                                                                                         | 2               | 4 | 3 |
| **Risks and Uncertainties [Abstract]**                                                                                                     |            |   |   |
| Advertising Expense                                                                                                                        | $ 78            | $ 71 | $ 63 |
| Foreign Currency Transaction Gain (Loss), before Tax                                                                                       | (25)            | 4 | 7 |
| Customer Concentration Risk [Domain]                                                                                                       |            |   |   |
| **Risks and Uncertainties [Abstract]**                                                                                                     |            |   |   |
| Concentration Risk Number of Customers                                                                                                     | 1               |   |   |
| Number Of Employees Hourly Workers [Member] | Unionized Employees Concentration Risk [Member]                                              |            |   |   |
| **Risks and Uncertainties [Abstract]**                                                                                                     |            |   |   |
| Concentration Risk Number Of Employees                                                                                                     | 4,600           |   |   |
| concentration risk number of employees percentage                                                                                          | 48.00%          |   |   |
| Number of Employees Salaried Workers [Member] | Unionized Employees Concentration Risk [Member]                                            |            |   |   |
| **Risks and Uncertainties [Abstract]**                                                                                                     |            |   |   |
| Concentration Risk Number Of Employees                                                                                                     | 400             |   |   |
| concentration risk number of employees percentage                                                                                          | 5.00%           |   |   |
| Pension Costs [Member] | Adjustment Year 2009 [Member]                                                                                     |            |   |   |
| **Accounting Policies [Line Items]**                                                                                                       |            |   |   |
| Quantifying Misstatement in Current Year Financial Statements, Amount                                                                      |            |   | 3 |
| Pension Costs [Member] | Adjustment Year 2008 [Member]                                                                                     |            |   |   |
| **Accounting Policies [Line Items]**                                                                                                       |            |   |   |
| Quantifying Misstatement in Current Year Financial Statements, Amount                                                                      |            |   | 2 |
| Deferred Tax Assets [Member]                                                                                                               |            |   |   |
| **Accounting Policies [Line Items]**                                                                                                       |            |   |   |
| Quantifying Misstatement in Current Year Financial Statements, Amount                                                                      |            |   | 5 |
| Value Added Tax [Member]                                                                                                                   |            |   |   |
| **Accounting Policies [Line Items]**                                                                                                       |            |   |   |
| Valuation Allowance, Deferred Tax Asset, Change in Amount                                                                                  |            |   | 42 |
| Earnings Per Share, Diluted For VAT tax adjustment                                                                                         |            |   | $ 0.58 |
| Correction Of Errors And Effect Of New Accounting Guidance Adoption [Member]                                                               |            |   |   |
| **Accounting Policies [Line Items]**                                                                                                       |            |   |   |
| Restatement of Prior Year Income, Net of Tax                                                                                               |            |   | $ (10) |

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Earnings Per Share, Diluted For VAT tax adjustment
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VAT Tax Adjustment
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| - Definition
Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.
+ References
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| - Definition
The aggregate foreign currency transaction gain (loss) (both realized and unrealized) included in determining net income for the reporting period. Excludes foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements. For certain enterprises, primarily banks, that are dealers in foreign exchange, foreign currency transaction gains (losses) may be disclosed as dealer gains (losses).
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| - Definition
Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.
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| - Definition
Amount of each individual error being corrected in the correcting adjustment.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Resulting effect of restatement to correct an error, after tax effects, on the net income of prior periods for the year in which any adjustments are first made. In statements containing more than one period, discloses the effects for each period.
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