Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)		9 Months Ended
	Sep. 30, 2020	Sep. 18, 2020	Sep. 30, 2019
Cash flows from operating activities
Net income (loss)	$ 2,758,000	$ (1,432,578,000)	$ 193,880,000
Adjustments to reconcile net income (loss) to cash flows from operating activities
Noncash reorganization items, net	0	810,909,000	0
Depletion, depreciation, and amortization	5,283,000	188,593,000	170,625,000
Write-down of oil and natural gas properties	0	996,658,000	0
Deferred income taxes	6,000	(408,869,000)	90,454,000
Stock-based compensation	0	4,111,000	9,866,000
Commodity derivatives expense (income)	(4,035,000)	(102,032,000)	15,462,000
Receipt on settlements of commodity derivatives	6,660,000	81,396,000	14,714,000
Gain on debt extinguishment	0	(18,994,000)	(106,220,000)
Debt issuance costs and discounts	114,000	11,571,000	7,607,000
Other, net	589,000	439,000	(6,862,000)
Changes in assets and liabilities, net of effects from acquisitions
Accrued production receivable	38,537,000	26,575,000	(1,428,000)
Trade and other receivables	1,366,000	(22,343,000)	(147,000)
Other current and long-term assets	705,000	743,000	27,000
Accounts payable and accrued liabilities	(7,980,000)	(16,102,000)	(33,167,000)
Oil and natural gas production payable	(11,064,000)	(6,792,000)	(1,819,000)
Other liabilities	(29,000)	123,000	(9,414,000)
Net cash provided by operating activities	32,910,000	113,408,000	343,578,000
Cash flows from investing activities
Oil and natural gas capital expenditures	(2,125,000)	(99,582,000)	(204,904,000)
Pipelines and plants capital expenditures	(6,000)	(11,601,000)	(25,965,000)
Net proceeds from sales of oil and natural gas properties and equipment	880,000	41,322,000	10,494,000
Other	(309,000)	12,747,000	5,797,000
Net cash used in investing activities	(1,560,000)	(57,114,000)	(214,578,000)
Cash flows from financing activities
Bank repayments	(55,000,000)	(551,000,000)	(641,000,000)
Bank borrowings	0	691,000,000	691,000,000
Interest payments treated as a reduction of debt	0	(46,417,000)	(59,808,000)
Cash paid in conjunction with debt repurchases	0	(14,171,000)	0
Cash paid in conjunction with debt exchange	0	0	(125,268,000)
Costs of debt financing	0	(12,482,000)	(11,017,000)
Pipeline financing and capital lease debt repayments	(54,000)	(51,792,000)	(10,279,000)
Other	0	(9,363,000)	5,470,000
Net cash provided by (used in) financing activities	(55,054,000)	5,775,000	(150,902,000)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(23,704,000)	62,069,000	(21,902,000)
Cash, cash equivalents, and restricted cash at beginning of period	95,114,000	33,045,000	54,949,000
Cash, cash equivalents, and restricted cash at end of period	$ 71,410,000	$ 95,114,000	$ 33,047,000