Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities
Net loss	$ (130,935)	$ (12,068)	$ (279,704)	$ (45,503)
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation, depletion and amortization	28,021	22,252	82,018	63,765
Derivative losses	(23,601)	23,677	9,681	72,464
Impairment of oil and gas assets	147,686	0	261,001	0
Impairment of other assets	0	0	6,407	0
(Gain) loss on sale of assets	(141)	2,024	(631)	2,599
Other			3,630	4,376
Change in assets and liabilities
Accounts receivable			20,446	(6,743)
Inventories			144	(1,415)
Prepaid expenses and other assets			645	322
Accounts payable and accrued liabilities			(24,685)	(12,383)
Revenue distribution payable			(9,950)	10,895
Deferred compensation			1,534	7,890
Net cash provided by operating activities			70,536	96,267
Cash flows from investing activities
Expenditures for property, plant, and equipment and oil and natural gas properties			(202,830)	(252,731)
Proceeds from asset dispositions			14,333	36,335
Proceeds from (payments on) derivative instruments, net			5,536	(16,642)
Net cash used in investing activities			(182,961)	(233,038)
Cash flows from financing activities
Proceeds from long-term debt			110,000	116,000
Repayment of long-term debt			(8,682)	(243,554)
Proceeds from Senior Notes			0	300,000
Principal payments under financing lease obligations			(2,002)	(2,003)
Payment of debt issuance costs and other financing fees			(20)	(7,572)
Debt extinguishment costs			(1,602)	0
Cash settlements of stock based awards			(10)	0
Treasury stock purchased			(1,171)	(4,872)
Net cash provided by financing activities			96,513	157,999
Net (decrease) increase in cash and cash equivalents			(15,912)	21,228
Cash and cash equivalents, at beginning of period			37,446	27,732
Cash and cash equivalents, at end of period	$ 21,534	$ 48,960	$ 21,534	$ 48,960