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Financial Instruments - Effect of Net Investment Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Foreign exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income	$ 26	$ (10)	$ (18)
Foreign exchange contracts | Other (income) expense, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing	(19)	(31)	(11)
Euro-denominated notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other Comprehensive Income	385	(75)	(183)
Euro-denominated notes | Other (income) expense, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Amount of Pretax (Gain) Loss Recognized in Other (income) expense, net for Amounts Excluded from Effectiveness Testing	$ 0	$ 0	$ 0

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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=121590274&loc=SL109998896-113959

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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=121590274&loc=SL109998896-113959

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