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AVAILABLE-FOR-SALE DEBT SECURITIES - Summary of the Balance Sheet Classification of Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions | Sep. 30, 2021 | Dec. 31, 2020
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Available-for-Sale Debt Securities |  |
Total | $ 2,489 | $ 2,026
Cash and cash equivalents |  |
Available-for-Sale Debt Securities |  |
Total | 14 | 113
Short-term marketable securities |  |
Available-for-Sale Debt Securities |  |
Total | 1,376 | 1,411
Long-term marketable securities |  |
Available-for-Sale Debt Securities |  |
Total | $ 1,099 | $ 502

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- Definition Amount excluding accrued interest, 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/2009/role/commonPracticeRef -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 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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