Investments (Fair Values by Classification) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Fair values of available-for-sale investments by classification in the Consolidated Balance Sheets
Marketable securities	$ 3,273	$ 2,874
Total interest-bearing securities	11,589	8,234
Available-for-sale investments [Member]
Fair values of available-for-sale investments by classification in the Consolidated Balance Sheets
Cash and cash equivalents	8,316	5,360
Marketable securities	3,273	2,874
Total interest-bearing securities	$ 11,589	$ 8,234

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Fair value portion 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.

+ References

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