v2.4.0.6

Fair Value Measurements and Financial Instruments (Details) (USD $) In Millions, except Per Share data, unless otherwise specified | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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Dec. 31, 2011 | Dec. 31, 2011 Fair Value Money market funds and highly liquid debt securities Recurring | Dec. 31, 2010 Fair Value Money market funds and highly liquid debt securities Recurring | Dec. 31, 2011 Fair Value Corporate bonds Recurring | Dec. 31, 2010 Fair Value Corporate bonds Recurring | Dec. 31, 2011 Fair Value Government bonds. Recurring | Dec. 31, 2010 Fair Value Government bonds. Recurring | Dec. 31, 2011 Fair Value Interest rate contracts Recurring | Dec. 31, 2010 Fair Value Interest rate contracts Recurring | Dec. 31, 2011 Fair Value Foreign exchange contracts Recurring | Dec. 31, 2010 Fair Value Foreign exchange contracts Recurring | Dec. 31, 2011 Quoted Prices in Active Markets for Identical Assets (Level 1) Money market funds and highly liquid debt securities Recurring | Dec. 31, 2010 Quoted Prices in Active Markets for Identical Assets (Level 1) Money market funds and highly liquid debt securities Recurring | Dec. 31, 2011 Significant Other Observable Inputs (Level 2) Money market funds and highly liquid debt securities Recurring | Dec. 31, 2010 Significant Other Observable Inputs (Level 2) Money market funds and highly liquid debt securities Recurring | Dec. 31, 2011 Significant Other Observable Inputs (Level 2) Government bonds. Recurring | Dec. 31, 2010 Significant Other Observable Inputs (Level 2) Government bonds. Recurring | Dec. 31, 2011 Significant Other Observable Inputs (Level 2) Interest rate contracts Recurring | Dec. 31, 2010 Significant Other Observable Inputs (Level 2) Interest rate contracts Recurring | Dec. 31, 2011 Significant Other Observable Inputs (Level 2) Foreign exchange contracts Recurring | Dec. 31, 2010 Significant Other Observable Inputs (Level 2) Foreign exchange contracts Recurring | Dec. 31, 2011 Significant Unobservable (Level 3) Inputs Corporate bonds Recurring | Dec. 31, 2010 Significant Unobservable (Level 3) Inputs Corporate bonds Recurring
Fair Value Measurements and Financial Instruments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net assets value (in dollar per share) | $ 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Money market funds and highly liquid debt securities |  | $ 2,428 | $ 2,618 |  |  |  |  |  |  |  |  | $ 2,403 | $ 2,591 | $ 25 | $ 27 |  |  |  |  |  |  |  |
Other investments |  |  |  | 12 | 12 | 3 | 3 |  |  |  |  |  |  |  |  | 3 | 3 |  |  |  |  | 12 | 12
Derivatives |  |  |  |  |  |  |  | 16 | 15 | 141 | 159 |  |  |  |  |  |  | 16 | 15 | 141 | 159 |  |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives |  |  |  |  |  |  |  |  |  | $ 189 | $ 158 |  |  |  |  |  |  |  |  | $ 189 | $ 158 |  |

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