Segment Information Reconciliation of Earnings Before Income Tax (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (Loss)	$ 59,684	$ 1,098,668	$ 118,581
Gain on Certain Asset Sales	(2,862)	14,571	(3,825)
Gain on Certain Asset Sales	35,563	157,015	188,063
Loss on Debt Extinguishment	(7,614)	(54,118)	(2,129)
Impairment of Other Intangible Assets	0	(18,650)	0
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (Loss)	26,211	378,427	(63,527)
Corporate, Non-Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (Loss)	33,473	720,241	182,108
Gain on Certain Asset Sales	(1,396)	14,571	(3,826)
Gain on Certain Asset Sales	42,483	154,775	188,063
Gain on Previously Held Equity Interest	0	623,663	0
Loss on Debt Extinguishment	(7,614)	(54,118)	(2,129)
Impairment of Other Intangible Assets	0	(18,650)	0
Exploration and Production Equipment \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (Loss)	(140,443)	244,616	(63,527)
Midstream \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (Loss)	$ 166,654	$ 133,811	$ 0

Amount of gain (loss) on sale or disposal of an equity method investment.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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