Investments - Fair Values by Classification (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Consolidated Balance Sheets locations
Cash and cash equivalents	$ 6,037	$ 6,945
Marketable securities	2,874	22,359
Total available-for-sale investments	8,234	28,724
Available-for-sale investments [Member]
Consolidated Balance Sheets locations
Cash and cash equivalents	5,360	6,365
Marketable securities	2,874	22,359
Total available-for-sale investments	$ 8,234	$ 28,724

Fair values of available-for-sale investments by classification in the Consolidated Balance Sheets.

No definition available.

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- Definition

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

+ References

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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), classified as current.

+ References

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

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