Financial Instruments, Derivatives and Fair Value Measures - Bases of Measurement (Details) - Recurring - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Fair value, asset and liability measures
Equity securities	$ 343	$ 357
Interest rate swap derivative financial instruments, assets	243	48
Foreign currency forward exchange contracts	170	148
Total Assets	756	553
Fair value of hedged long-term debt	3,082	2,890
Foreign currency forward exchange contracts	105	89
Contingent consideration related to business combinations	68	68
Total Liabilities	3,255	3,047
Quoted Prices in Active Markets
Fair value, asset and liability measures
Equity securities	343	357
Total Assets	343	357
Significant Other Observable Inputs
Fair value, asset and liability measures
Interest rate swap derivative financial instruments, assets	243	48
Foreign currency forward exchange contracts	170	148
Total Assets	413	196
Fair value of hedged long-term debt	3,082	2,890
Foreign currency forward exchange contracts	105	89
Total Liabilities	3,187	2,979
Significant Unobservable Inputs
Fair value, asset and liability measures
Contingent consideration related to business combinations	68	68
Total Liabilities	$ 68	$ 68

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

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Amount of liability hedged in fair value hedging relationship.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value of financial and nonfinancial obligations.

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