v3.20.1

Derivative Financial Instruments (Derivatives And Hedging-Overall-Subsequent Measurement) (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | $ (84,745) | $ 69,065 | $ (27,770)
Sales [Member] | Commodity Contract [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | (72,562) | 85,012 | (56,338)
Cost of Sales [Member] | Commodity Contract [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | (1,931) | (15,947) | 25,566
Operating Expenses [Member] | Commodity Contract [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | 0 | 3,002
Other Operating Income (Expense) [Member] | Energy Related Derivative [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | $ (10,252) | $ 0 | $ 0

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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=109980867&loc=SL5618551-113959 + 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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