| **Derivative Financial Instruments and Risk Management (Details 2) (USD $)In Millions, unless otherwise specified** | Jun. 30, 2013 | Dec. 31, 2012 |
|---------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset Fair Value                                                                                                    | $ 170         | $ 238         |
| Liability Fair Value                                                                                                | (9)           | (15)          |
| Designated derivatives                                                                                              |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset (Liability) Fair Value                                                                                        | 147           | 218           |
| Designated derivatives | Interest rate contracts | Other assets                                                     |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset Fair Value                                                                                                    | 153           | 226           |
| Designated derivatives | Interest rate contracts | Accrued expenses                                                 |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Liability Fair Value                                                                                                | (6)           | (8)           |
| Undesignated derivatives                                                                                            |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset (Liability) Fair Value                                                                                        | 14            | 5             |
| Undesignated derivatives | Interest rate contracts | Other assets                                                   |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset Fair Value                                                                                                    | 1             | 2             |
| Undesignated derivatives | Interest rate contracts | Accrued expenses                                               |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Liability Fair Value                                                                                                | 0             | (1)           |
| Undesignated derivatives | Foreign exchange contracts | Other assets                                                |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset Fair Value                                                                                                    | 10            | 10            |
| Undesignated derivatives | Foreign exchange contracts | Accrued expenses                                            |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Liability Fair Value                                                                                                | (3)           | (5)           |
| Undesignated derivatives | Cross currency contracts | Other assets                                                  |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Asset Fair Value                                                                                                    | 6             | 0             |
| Undesignated derivatives | Cross currency contracts | Accrued expenses                                              |          |          |
| **Derivatives, Fair Value**                                                                                         |          |          |
| Liability Fair Value                                                                                                | $ 0           | $ (1)         |

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| - Definition
Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph a -Clause 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph a -Clause 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959
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| - Definition
Fair value of the assets less the liabilities of a derivative or group of derivatives.
+ References
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