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DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Customer Supply Agreements [Member] | Sales [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | $ 122 | $ 78 | $ 426

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959 + Details
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