CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) (in thousands, except per share data) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Operating revenues and other income:
Oil, gas, and NGL production revenue		$ 169,790	$ 406,854	$ 524,023	$ 747,330
Net gain on divestiture activity		91	262	91	323
Other operating revenues		(249)	56	1,252	449
Total operating revenues and other income		169,632	407,172	525,366	748,102
Operating expenses:
Oil, gas, and NGL production expense		80,445	123,050	199,997	244,355
Depletion, depreciation, amortization, and asset retirement obligation liability accretion		180,856	206,330	414,345	384,076
Exploration		9,787	10,877	21,136	22,225
Impairment	[1]	8,750	12,417	998,513	18,755
General and administrative		27,227	30,920	54,674	63,006
Net derivative (gain) loss		167,200	(79,655)	(378,140)	97,426
Other operating (income) expense, net		8,046	(934)	8,612	(599)
Total operating expenses		482,311	303,005	1,319,137	829,244
Income (loss) from operations		(312,679)	104,167	(793,771)	(81,142)
Interest expense		(40,354)	(39,627)	(81,866)	(77,607)
Gain on extinguishment of debt		227,281	0	239,476	0
Other non-operating expense, net		(185)	(562)	(679)	(879)
Income (loss) before income taxes		(125,937)	63,978	(636,840)	(159,628)
Income tax (expense) benefit		36,685	(13,590)	135,693	32,448
Net income (loss)		$ (89,252)	$ 50,388	$ (501,147)	$ (127,180)
Basic weighted-average common shares outstanding		113,008	112,262	113,015	112,257
Diluted weighted-average common shares outstanding		113,008	112,932	113,015	112,257
Basic net income (loss) per common share		$ (0.79)	$ 0.45	$ (4.43)	$ (1.13)
Diluted net income (loss) per common share		(0.79)	0.45	(4.43)	(1.13)
Dividends per common share		$ 0	$ 0	$ 0.01	$ 0.05

[1] ⁽²⁾ Amounts may not calculate due to rounding.