Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
Oil and natural gas	$ 85,470	$ 78,854	$ 256,241	$ 206,318
Contract drilling	51,619	25,819	128,059	88,786
Gas gathering and processing	51,399	48,735	150,493	132,793
Total revenues	188,488	153,408	534,793	427,897
Operating costs:
Oil and natural gas	33,911	26,014	95,873	92,691
Contract drilling	34,747	19,137	91,213	66,489
Gas gathering and processing	38,116	35,738	111,862	99,185
Total operating costs	106,774	80,889	298,948	258,365
Depreciation, depletion, and amortization	54,533	49,969	151,545	158,437
Impairments (Note 2)	0	49,443	0	161,563
General and administrative	9,235	8,852	26,902	25,811
Gain on disposition of assets	(81)	(154)	(1,153)	(823)
Total operating expenses	170,461	188,999	476,242	603,353
Income (loss) from operations	18,027	(35,591)	58,551	(175,456)
Other income (expense):
Interest, net	(9,944)	(10,002)	(28,807)	(30,225)
Gain (loss) on derivatives	(2,614)	6,969	21,019	(4,774)
Other, net	5	3	14	(11)
Total other income (expense)	(12,553)	(3,030)	(7,774)	(35,010)
Income (loss) before income taxes	5,474	(38,621)	50,777	(210,466)
Income tax expense (benefit):
Deferred	1,769	(14,599)	22,084	(73,159)
Total income taxes	1,769	(14,599)	22,084	(73,159)
Net income (loss)	$ 3,705	$ (24,022)	$ 28,693	$ (137,307)
Net income (loss) per common share:
Basic	$ 0.07	$ (0.48)	$ 0.56	$ (2.75)
Diluted	$ 0.07	$ (0.48)	$ 0.56	$ (2.75)