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Derivatives and Risk Management Activities - Financial Impact (Details) - Derivatives Not Designated as a Hedge - Commodity derivatives - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Impact of derivative activities recognized in earnings |  |  |
Total gain (loss) on derivatives recognized in net income | $ (297) | $ 324 | $ 148
Supply and Logistics segment revenues |  |  |
Impact of derivative activities recognized in earnings |  |  |
Total gain (loss) on derivatives recognized in net income | (302) | 310 | 150
Field operating costs |  |  |
Impact of derivative activities recognized in earnings |  |  |
Total gain (loss) on derivatives recognized in net income | $ 5 | $ 14 | $ (2)

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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