Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues:
Crude oil, natural gas and NGLs sales	$ 314,920	$ 307,409	$ 809,156	$ 967,464
Commodity price risk management gain (loss), net	(68,061)	54,867	245,851	(87,858)
Other income	2,358	3,667	5,656	11,495
Total revenues	249,217	365,943	1,060,663	891,101
Costs, expenses and other:
Lease operating expenses	37,338	36,498	122,680	106,047
Production taxes	14,621	13,039	40,937	57,849
Transportation, gathering and processing expenses	24,399	10,999	54,844	34,631
Exploration, geologic and geophysical expense	162	209	1,026	3,492
General and administrative expense	32,490	41,091	130,007	123,497
Depreciation, depletion and amortization	144,504	171,839	470,152	491,784
Accretion of asset retirement obligations	2,420	1,356	7,398	4,503
Impairment of properties and equipment	1,221	167	882,327	37,021
Loss (gain) on sale of properties and equipment	(289)	43,872	(642)	9,599
Other expenses	1,936	2,492	6,083	8,882
Total cost, expenses and other	258,802	321,562	1,714,812	877,305
Income (loss) from operations	(9,585)	44,381	(654,149)	13,796
Interest expense	(21,022)	(17,811)	(66,977)	(53,679)
Income (loss) before income taxes	(30,607)	26,570	(721,126)	(39,883)
Income tax (expense) benefit	(176)	(10,662)	3,496	4,163
Net income (loss)	$ (30,783)	$ 15,908	$ (717,630)	$ (35,720)
Earnings per share:
Basic	$ (0.31)	$ 0.25	$ (7.34)	$ (0.55)
Diluted	$ (0.31)	$ 0.25	$ (7.34)	$ (0.55)
Weighted-average common shares outstanding
Basic	99,617	62,547	97,762	64,835
Diluted	99,617	62,595	97,762	64,835