Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (Unaudited) - 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
Revenues	$ 115,405	$ 163,295	$ 339,513	$ 460,332
OPERATING EXPENSES
Lease operating	11,494	11,986	33,436	29,651
Transportation, gathering and compression	$ 51,961	$ 57,027	$ 157,472	$ 150,065
Cost, Product and Service [Extensible List]	us-gaap:NaturalGasGatheringTransportationMarketingAndProcessingMember	us-gaap:NaturalGasGatheringTransportationMarketingAndProcessingMember	us-gaap:NaturalGasGatheringTransportationMarketingAndProcessingMember	us-gaap:NaturalGasGatheringTransportationMarketingAndProcessingMember
Production and ad valorem taxes	$ 3,677	$ 1,660	$ 10,146	$ 8,519
Brokered natural gas and marketing expense	7,345	10,574	24,349	32,017
Depreciation, depletion, amortization and accretion	53,153	45,456	140,058	113,950
Exploration	11,767	16,621	34,112	48,602
General and administrative	12,144	14,580	33,594	57,074
Rig termination and standby	303	1,221	303	1,221
Gain on sale of assets	(62)	(733)	(1,419)	(731)
Other expense	87	2	121	40
Total operating expenses	151,869	158,394	432,172	440,408
OPERATING INCOME (LOSS)	(36,464)	4,901	(92,659)	19,924
OTHER INCOME (EXPENSE)
Gain (loss) on derivative instruments	(40,535)	15,812	(11,329)	40,620
Interest expense, net	(14,402)	(15,192)	(44,166)	(44,140)
Other income	2		19	8
Total other income (expense), net	(54,935)	620	(55,476)	(3,512)
INCOME (LOSS) FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	(91,399)	5,521	(148,135)	16,412
INCOME (LOSS) FROM CONTINUING OPERATIONS	(91,399)	5,521	(148,135)	16,412
Income (loss) from discontinued operations, net of income tax	(801)	(1,237)	(10,092)	1,286
NET INCOME (LOSS)	$ (92,200)	$ 4,284	$ (158,227)	$ 17,698
Basic:
Weighted average common stock outstanding	36,035	35,684	35,889	32,343
Income (loss) from continuing operations	$ (2.54)	$ 0.15	$ (4.13)	$ 0.51
Income (loss) from discontinued operations	(0.02)	(0.03)	(0.28)	0.04
Net income (loss)	$ (2.56)	$ 0.12	$ (4.41)	$ 0.55
Diluted:
Weighted average common stock outstanding	36,035	35,697	35,889	32,471
Income (loss) from continuing operations	$ (2.54)	$ 0.15	$ (4.13)	$ 0.51
Income (loss) from discontinued operations	(0.02)	(0.03)	(0.28)	0.04
Net income (loss)	$ (2.56)	$ 0.12	$ (4.41)	$ 0.55
Oil and Gas [Member]
REVENUES
Revenues	$ 108,518	$ 153,021	$ 315,471	$ 428,278
Brokered Natural Gas and Marketing Revenue [Member]
REVENUES
Revenues	6,831	10,228	23,859	31,747
Other Revenue [Member]
REVENUES
Revenues	$ 56	$ 46	$ 183	$ 307