Derivative Instruments - Fair value gains (losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Summary of realized and unrealized gains (losses) on derivative instruments
Derivative fair value (gains) losses	$ (177,756)	$ 565,833
Commodity derivative \| Revenue
Summary of realized and unrealized gains (losses) on derivative instruments
Derivative fair value (gains) losses	(169,967)	$ 565,833
Embedded derivatives \| Revenue
Summary of realized and unrealized gains (losses) on derivative instruments
Derivative fair value (gains) losses	$ (7,789)

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109998890-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959

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Period Type:	duration