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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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value of financial and nonfinancial obligations.

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Amount of noncurrent assets classified as other.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Assets
Investments	$ 64	$ 1,785
Publicly traded equity securities	779	838
Derivative assets	710	288
Liabilities
Contingent consideration	694	767	$ 667	$ 788
Derivative liabilities	93	97
Foreign government bonds
Assets
Investments	2	0
Corporate notes and bonds
Assets
Investments	0	621
Commercial paper
Assets
Investments	0	668
Asset-backed securities
Assets
Investments	$ 0	227
Liabilities
Primary weighted average life of collateral	5 years
U.S. government and agency securities
Assets
Investments	$ 62	269
Fair Value, Measurements, Recurring
Assets
Investments	562	2,243
Other assets	281	380
Derivative assets	710	288
Total assets	1,553	2,911
Liabilities
Contingent consideration	694	767
Derivative liabilities	93	97
Total liabilities	787	864
Fair Value, Measurements, Recurring \| Foreign exchange contracts
Assets
Derivative assets	455	169
Liabilities
Derivative liabilities	90	95
Fair Value, Measurements, Recurring \| Interest rate swap contracts
Assets
Derivative assets	81	15
Fair Value, Measurements, Recurring \| Currency options
Assets
Derivative assets	174	104
Liabilities
Derivative liabilities	3	1
Fair Value, Measurements, Recurring \| Interest rate swap contracts
Liabilities
Derivative liabilities	0	1
Fair Value, Measurements, Recurring \| Level 1
Assets
Investments	560	518
Other assets	281	380
Derivative assets	0	0
Total assets	841	898
Liabilities
Contingent consideration	0	0
Derivative liabilities	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Foreign exchange contracts
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Interest rate swap contracts
Assets
Derivative assets	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Currency options
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Interest rate swap contracts
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 2
Assets
Investments	2	1,725
Other assets	0	0
Derivative assets	710	288
Total assets	712	2,013
Liabilities
Contingent consideration	0	0
Derivative liabilities	93	97
Total liabilities	93	97
Fair Value, Measurements, Recurring \| Level 2 \| Foreign exchange contracts
Assets
Derivative assets	455	169
Liabilities
Derivative liabilities	90	95
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate swap contracts
Assets
Derivative assets	81	15
Fair Value, Measurements, Recurring \| Level 2 \| Currency options
Assets
Derivative assets	174	104
Liabilities
Derivative liabilities	3	1
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate swap contracts
Liabilities
Derivative liabilities	0	1
Fair Value, Measurements, Recurring \| Level 3
Assets
Investments	0	0
Other assets	0	0
Derivative assets	0	0
Total assets	0	0
Liabilities
Contingent consideration	694	767
Derivative liabilities	0	0
Total liabilities	694	767
Fair Value, Measurements, Recurring \| Level 3 \| Foreign exchange contracts
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Interest rate swap contracts
Assets
Derivative assets	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Currency options
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Interest rate swap contracts
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Foreign government bonds
Assets
Investments	2	0
Fair Value, Measurements, Recurring \| Foreign government bonds \| Level 1
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Foreign government bonds \| Level 2
Assets
Investments	2	0
Fair Value, Measurements, Recurring \| Foreign government bonds \| Level 3
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Corporate notes and bonds
Assets
Investments	0	621
Fair Value, Measurements, Recurring \| Corporate notes and bonds \| Level 1
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Corporate notes and bonds \| Level 2
Assets
Investments	0	621
Fair Value, Measurements, Recurring \| Corporate notes and bonds \| Level 3
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Commercial paper
Assets
Investments	0	668
Fair Value, Measurements, Recurring \| Commercial paper \| Level 1
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Commercial paper \| Level 2
Assets
Investments	0	668
Fair Value, Measurements, Recurring \| Commercial paper \| Level 3
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Asset-backed securities
Assets
Investments	0	227
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 1
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 2
Assets
Investments	0	227
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 3
Assets
Investments	0	0
Fair Value, Measurements, Recurring \| U.S. government and agency securities
Assets
Investments	0	209
Other assets	62	60
Fair Value, Measurements, Recurring \| U.S. government and agency securities \| Level 1
Assets
Investments	0	0
Other assets	62	60
Fair Value, Measurements, Recurring \| U.S. government and agency securities \| Level 2
Assets
Investments	0	209
Other assets	0	0
Fair Value, Measurements, Recurring \| U.S. government and agency securities \| Level 3
Assets
Investments	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Publicly traded equity securities
Assets
Publicly traded equity securities	560	518
Other assets	219	320
Fair Value, Measurements, Recurring \| Publicly traded equity securities \| Level 1
Assets
Publicly traded equity securities	560	518
Other assets	219	320
Fair Value, Measurements, Recurring \| Publicly traded equity securities \| Level 2
Assets
Publicly traded equity securities	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Publicly traded equity securities \| Level 3
Assets
Publicly traded equity securities	0	0
Other assets	$ 0	$ 0