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Financial Instruments - Effect of Net Investment Hedges (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Foreign exchange contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income | $ (2) | $ 0
Foreign exchange contracts | Other (income) expense, net |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Income For Amounts Excluded from Effectiveness Testing | 0 | 0
Euro-denominated notes |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income | 178 | 135
Euro-denominated notes | Other (income) expense, net |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Income For Amounts Excluded from Effectiveness Testing | $ 0 | $ 0

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- Definition Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Before Reclassification, Pretax + References No definition available. + Details
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- Definition Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Reclassification, Pretax + References No definition available. + Details
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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. + References No definition available. + Details
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- Details
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