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FAIR VALUE MEASUREMENTS FAIR VALUE MEASUREMENTS - CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Available-for-sale Securities, Activity [Abstract] |  |  |
Proceeds from sales and maturities | $ 1,388 | $ 962 | $ 1,175

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- Definition Available-for-sale Securities, Activity [Abstract] + References No definition available. + Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27357-111563 + Details
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