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Financial Instruments - Effect of Net Investment Hedges (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
Foreign exchange contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income | $ (3) | $ (11)
Foreign exchange contracts | Other (income) expense, net |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing | (8) | (8)
Euro-denominated notes |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income | (51) | (30)
Euro-denominated notes | Other (income) expense, net |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing | $ 0 | $ 0

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- Definition Amount, before tax and reclassification, of gain (loss) from derivative designated and qualifying as net investment hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CCC -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998896-113959 + Details
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- Definition Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from derivative designated and qualifying as net investment hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CCC -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998896-113959 + Details
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