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Derivative Financial Instruments Gains and Losses (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2020 | Mar. 31, 2019
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | $ (73,437) | $ 4,969
Net derivative (gain) loss | (545,340) | 177,081
Oil Contracts [Member] |  |
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | (53,582) | 1,369
Net derivative (gain) loss | (542,540) | 185,797
Gas Contracts [Member] |  |
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | (14,625) | 4,134
Net derivative (gain) loss | 6,728 | (6,113)
NGL Contracts [Member] |  |
Derivative Instruments, (Gain) Loss [Line Items] |  |
Derivative settlement (gain) loss | (5,230) | (534)
Net derivative (gain) loss | $ (9,528) | $ (2,603)

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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=109980867&loc=SL5618551-113959 + Details
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