Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities
Net income (loss)	$ (623,458)	$ 121,018
Adjustments to reconcile net income (loss) to cash flows from operating activities
Depletion, depreciation, and amortization	152,276	115,561
Write-down of oil and natural gas properties	734,981	0
Deferred income taxes	(106,513)	52,545
Stock-based compensation	3,540	6,865
Commodity derivatives expense (income)	(106,641)	58,617
Receipt on settlements of commodity derivatives	70,267	6,657
Gain on debt extinguishment	(18,994)	(100,346)
Debt issuance costs and discounts	9,921	2,901
Other, net	(1,642)	(57)
Changes in assets and liabilities, net of effects from acquisitions
Accrued production receivable	62,063	(9,909)
Trade and other receivables	(16,162)	(271)
Other current and long-term assets	(4,552)	(3,389)
Accounts payable and accrued liabilities	(60,295)	(33,320)
Oil and natural gas production payable	(22,217)	1,746
Other liabilities	237	(5,618)
Net cash provided by operating activities	72,811	213,000
Cash flows from investing activities
Oil and natural gas capital expenditures	(79,897)	(148,254)
Pipelines and plants capital expenditures	(10,962)	(10,591)
Net proceeds from sales of oil and natural gas properties and equipment	40,971	431
Other	(105)	(725)
Net cash used in investing activities	(49,993)	(159,139)
Cash flows from financing activities
Bank repayments	(226,000)	(281,000)
Bank borrowings	491,000	361,000
Interest payments treated as a reduction of debt	(42,506)	(42,558)
Cash paid in conjunction with debt repurchases	(14,171)	0
Cash paid in conjunction with debt exchange	0	(120,007)
Costs of debt financing	(299)	(9,332)
Pipeline financing and capital lease debt repayments	(7,015)	(7,273)
Other	(9,230)	12,899
Net cash provided by (used in) financing activities	191,779	(86,271)
Net increase (decrease) in cash, cash equivalents, and restricted cash	214,597	(32,410)
Cash, cash equivalents, and restricted cash at beginning of period	33,045	54,949
Cash, cash equivalents, and restricted cash at end of period	$ 247,642	$ 22,539