Investments - Fair Values by Classification (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Consolidated Balance Sheets locations
Marketable securities	$ 48	$ 4,381
Total available-for-sale investments	7,304	9,845
Available-for-sale investments [Member]
Consolidated Balance Sheets locations
Cash and cash equivalents	7,256	5,464
Marketable securities	48	4,381
Total available-for-sale investments	$ 7,304	$ 9,845

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
-Topic 942
-SubTopic 210
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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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), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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-Section 45
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-URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26626-111562

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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

No definition available.

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