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Financial Instruments - Effect of Net Investment Hedges (Details) - USD ($) $ in Millions	3 Months Ended
	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

X

- Definition

Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Before Reclassification, Pretax

+ References

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+ Details

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X

- Definition

Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Reclassification, Pretax

+ References

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X

- 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.

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X

- Details

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X

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