Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues and other income		$ 301,368,000	$ 117,875,000	$ 552,527,000	$ 360,076,000
Expenses
Taxes other than income		22,382,000	10,372,000	41,345,000	30,058,000
General and administrative expenses		15,450,000	23,776,000	47,433,000	33,509,000
Interest, net of amounts capitalized of $1,168, $8,729, $2,251 and $18,181, respectively		1,252,000	20,617,000	2,788,000	40,563,000
Depletion, depreciation, and amortization		36,381,000	55,414,000	75,831,000	152,276,000
Commodity derivatives expense (income)		172,664,000	40,130,000	288,407,000	(106,641,000)
Gain on debt extinguishment		0	0	0	(18,994,000)
Write-down of oil and natural gas properties		0	662,440,000	14,377,000	734,981,000
Other expenses		3,214,000	11,290,000	5,360,000	13,784,000
Total expenses		379,359,000	917,055,000	700,402,000	1,095,856,000
Loss before income taxes		(77,991,000)	(799,180,000)	(147,875,000)	(735,780,000)
Income tax benefit		(296,000)	(101,706,000)	(538,000)	(112,322,000)
Net loss		$ (77,695,000)	$ (697,474,000)	$ (147,337,000)	$ (623,458,000)
Net loss per common share
Basic		$ (1.52)	$ (1.41)	$ (2.91)	$ (1.26)
Diluted		$ (1.52)	$ (1.41)	$ (2.91)	$ (1.26)
Weighted average common shares outstanding
Basic		50,999	495,245	50,661	494,752
Diluted	[1]	50,999	495,245	50,661	494,752
Other income
Revenues and other income		$ 707,000	$ 494,000	$ 1,067,000	$ 1,322,000
Transportation and marketing
Operating expenses		8,522,000	9,388,000	16,319,000	19,009,000
Oil, natural gas, and related product sales
Revenues and other income		282,708,000	109,387,000	518,153,000	339,011,000
Operating expenses		110,225,000	81,293,000	192,195,000	190,563,000
CO2
Revenues and other income		10,134,000	6,504,000	19,362,000	14,532,000
Operating expenses		1,531,000	885,000	2,524,000	1,637,000
Oil marketing
Revenues and other income		7,819,000	1,490,000	13,945,000	5,211,000
Operating expenses		$ 7,738,000	$ 1,450,000	$ 13,823,000	$ 5,111,000

[1] If the Company had recognized net income, the weighted average diluted shares outstanding would have been 54.3 million and 587.1 million for the three months ended June 30, 2021 and 2020, respectively, and 52.7 million and 586.6 million for the six months ended June 30, 2021 and 2020, respectively.