Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities
Net loss	$ (438,726)	$ (45,229)	$ (433,809)	$ (148,769)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities
Depreciation, depletion and amortization	14,821	30,282	37,833	53,997
Derivative (gains) losses	13,019	(17,734)	(65,361)	33,282
Impairment of oil and gas assets	384,639	63,593	456,010	113,315
Impairment of other assets	310	6,407	463	6,407
Write-off of Senior Note issuance costs	4,420	0	4,420	0
Loss (gain) on sale of assets	261	(491)	159	(490)
Other			4,612	1,621
Change in assets and liabilities
Accounts receivable			6,206	13,584
Inventories			747	40
Prepaid expenses and other assets			(1,277)	1,055
Accounts payable and accrued liabilities			(7,217)	(18,389)
Revenue distribution payable			(13,049)	600
Deferred compensation			844	1,852
Net cash (used in) provided by operating activities			(9,419)	58,105
Cash flows from investing activities
Expenditures for property, plant, and equipment and oil and natural gas properties			(86,862)	(146,434)
Proceeds from asset dispositions			3,370	857
Proceeds from derivative instruments, net			32,089	653
Net cash used in investing activities			(51,403)	(144,924)
Cash flows from financing activities
Proceeds from long-term debt			120,000	85,000
Repayment of long-term debt			(25,313)	(343)
Principal payments under financing lease obligations	(107)	(746)	(212)	(1,445)
Payment of debt issuance costs and other financing fees			(93)	(20)
Treasury stock purchased			(18)	(1,171)
Net cash provided by financing activities			94,364	82,021
Net increase (decrease) in cash and cash equivalents			33,542	(4,798)
Cash and cash equivalents, at beginning of period			22,595	37,446
Cash and cash equivalents, at end of period	$ 56,137	$ 32,648	$ 56,137	$ 32,648