Segment Information - Reconciliation of Segment Information, (Loss) Earnings Before Income Tax (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Earnings (Loss) Before Income Taxes for Reportable Business Segments	$ (457,804)	$ (76,210)
Other (Expense) Income	(5,186)	579
Gain on Certain Asset Sales	12,055	(3,085)
Gain (Loss) on Debt Extinguishment	11,263	(7,537)
Impairment of Goodwill	473,045	0
Loss Before Income Tax	(457,804)	(76,210)
Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Earnings (Loss) Before Income Taxes for Reportable Business Segments	(476,097)	(73,846)
Loss Before Income Tax	(476,097)	(73,846)
Corporate, Non-Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Earnings (Loss) Before Income Taxes for Reportable Business Segments	18,293	(2,364)
Other (Expense) Income	(5,013)	1,030
Gain on Certain Asset Sales	12,043	4,143
Gain (Loss) on Debt Extinguishment	11,263	(7,537)
Loss Before Income Tax	18,293	(2,364)
Total E&P \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Earnings (Loss) Before Income Taxes for Reportable Business Segments	(46,553)	(106,430)
Loss Before Income Tax	(46,553)	(106,430)
Midstream \| Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Total Segment Earnings (Loss) Before Income Taxes for Reportable Business Segments	(429,544)	32,584
Loss Before Income Tax	$ (429,544)	$ 32,584

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of income (expense) related to nonoperating activities, classified as other.

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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.

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