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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	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assets
Investments, debt securities	$ 1,785	$ 7,261
Publicly traded equity securities	838	456
Derivative assets	288	454
Liabilities
Contingent consideration	767	788	$ 935
Derivative liabilities	97	160
Corporate notes and bonds
Assets
Investments, debt securities	621	4,920
Asset-backed securities
Assets
Investments, debt securities	$ 227	1,275
Liabilities
Primary weighted-average lives of investment collateral (or less)	5 years
U.S. government and agency securities
Assets
Investments, debt securities	$ 269	892
Foreign government bonds
Assets
Investments, debt securities	0	166
Mortgage-backed securities
Assets
Investments, debt securities	0	8
Fair Value, Measurements, Recurring
Assets
Investments	2,243	7,132
Other assets	380	585
Derivative assets	288	454
Total assets	2,911	8,171
Liabilities
Contingent consideration	767	788
Derivative liabilities	97	160
Total liabilities	864	948
Fair Value, Measurements, Recurring \| Interest rate swap contracts
Assets
Derivative assets	15	0
Liabilities
Derivative liabilities	1	81
Fair Value, Measurements, Recurring \| Foreign exchange contracts
Assets
Derivative assets	169	241
Liabilities
Derivative liabilities	95	74
Fair Value, Measurements, Recurring \| Purchased currency options
Assets
Derivative assets	104	213
Liabilities
Derivative liabilities	1	5
Fair Value, Measurements, Recurring \| Commercial paper
Assets
Investments, debt securities	668	0
Fair Value, Measurements, Recurring \| Corporate notes and bonds
Assets
Investments, debt securities	621	4,835
Other assets	0	85
Fair Value, Measurements, Recurring \| Asset-backed securities
Assets
Investments, debt securities	227	1,253
Other assets	0	22
Fair Value, Measurements, Recurring \| U.S. government and agency securities
Assets
Investments, debt securities	209	731
Other assets	60	161
Fair Value, Measurements, Recurring \| Foreign government bonds
Assets
Investments, debt securities	0	166
Fair Value, Measurements, Recurring \| Mortgage-backed securities
Assets
Other assets	0	8
Fair Value, Measurements, Recurring \| Publicly traded equity securities
Assets
Publicly traded equity securities	518	147
Other assets	320	309
Fair Value, Measurements, Recurring \| Level 1
Assets
Investments	518	147
Other assets	380	364
Derivative assets	0	0
Total assets	898	511
Liabilities
Contingent consideration	0	0
Derivative liabilities	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Interest rate swap contracts
Assets
Derivative assets	0	0
Liabilities
Derivative 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 \| Purchased currency options
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Commercial paper
Assets
Investments, debt securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Corporate notes and bonds
Assets
Investments, debt securities	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Asset-backed securities
Assets
Investments, debt securities	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 1 \| U.S. government and agency securities
Assets
Investments, debt securities	0	0
Other assets	60	55
Fair Value, Measurements, Recurring \| Level 1 \| Foreign government bonds
Assets
Investments, debt securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Mortgage-backed securities
Assets
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Publicly traded equity securities
Assets
Publicly traded equity securities	518	147
Other assets	320	309
Fair Value, Measurements, Recurring \| Level 2
Assets
Investments	1,725	6,985
Other assets	0	221
Derivative assets	288	454
Total assets	2,013	7,660
Liabilities
Contingent consideration	0	0
Derivative liabilities	97	160
Total liabilities	97	160
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate swap contracts
Assets
Derivative assets	15	0
Liabilities
Derivative liabilities	1	81
Fair Value, Measurements, Recurring \| Level 2 \| Foreign exchange contracts
Assets
Derivative assets	169	241
Liabilities
Derivative liabilities	95	74
Fair Value, Measurements, Recurring \| Level 2 \| Purchased currency options
Assets
Derivative assets	104	213
Liabilities
Derivative liabilities	1	5
Fair Value, Measurements, Recurring \| Level 2 \| Commercial paper
Assets
Investments, debt securities	668	0
Fair Value, Measurements, Recurring \| Level 2 \| Corporate notes and bonds
Assets
Investments, debt securities	621	4,835
Other assets	0	85
Fair Value, Measurements, Recurring \| Level 2 \| Asset-backed securities
Assets
Investments, debt securities	227	1,253
Other assets	0	22
Fair Value, Measurements, Recurring \| Level 2 \| U.S. government and agency securities
Assets
Investments, debt securities	209	731
Other assets	0	106
Fair Value, Measurements, Recurring \| Level 2 \| Foreign government bonds
Assets
Investments, debt securities	0	166
Fair Value, Measurements, Recurring \| Level 2 \| Mortgage-backed securities
Assets
Other assets	0	8
Fair Value, Measurements, Recurring \| Level 2 \| Publicly traded equity securities
Assets
Publicly traded equity securities	0	0
Other assets	0	0
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	767	788
Derivative liabilities	0	0
Total liabilities	767	788
Fair Value, Measurements, Recurring \| Level 3 \| Interest rate swap contracts
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
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 \| Purchased currency options
Assets
Derivative assets	0	0
Liabilities
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Commercial paper
Assets
Investments, debt securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Corporate notes and bonds
Assets
Investments, debt securities	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Asset-backed securities
Assets
Investments, debt securities	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. government and agency securities
Assets
Investments, debt securities	0	0
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Foreign government bonds
Assets
Investments, debt securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Mortgage-backed securities
Assets
Other assets	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Publicly traded equity securities
Assets
Publicly traded equity securities	0	0
Other assets	$ 0	$ 0