Fair value measurements Summary of Classification on Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities
Total	$ 7,562	$ 5,688
Cash and cash equivalents
Fair Value, Assets and Liabilities
Marketable equity securities	7,069	5,305
Prepaid Expenses and Other Current Assets
Fair Value, Assets and Liabilities
Marketable equity securities	319	241
Other long-term assets
Fair Value, Assets and Liabilities
Marketable equity securities	$ 174	$ 142

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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+ References

No definition available.

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