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Derivative Financial Instruments Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	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

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- Definition

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+ References

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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

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