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Derivative Financial Instruments Gains and Losses (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | $ 107,885 | $ (73,437)
Net derivative (gain) loss | 344,689 | (545,340)
Oil Contracts [Member] |  |
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | 56,329 | (53,582)
Net derivative (gain) loss | 265,815 | (542,540)
Gas Contracts [Member] |  |
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | 40,448 | (14,625)
Net derivative (gain) loss | 48,922 | 6,728
NGL Contracts [Member] |  |
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | 11,108 | (5,230)
Net derivative (gain) loss | $ 29,952 | $ (9,528)

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- Definition Realized gain or loss recognized in earnings from the settlement of derivative instruments not designated as hedges. + References No definition available. + 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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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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