Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues
Oil and natural gas	$ 385,774	$ 740,079	$ 649,718
Contract drilling	265,668	476,517	414,778
Gas gathering and processing	202,789	356,348	287,354
Total revenues	854,231	1,572,944	1,351,850
Oil and natural gas
Operating costs	166,046	187,916	184,001
Depreciation, depletion, and amortization	251,944	276,088	226,498
Impairment of oil and natural gas properties (Note 2)	1,599,348	76,683	0
Contract drilling
Operating costs	156,408	274,933	247,280
Depreciation	56,135	85,370	71,194
Impairment of contract drilling equipment (Note 2)	8,314	74,318	0
Gas gathering and processing
Operating costs	161,556	306,831	243,406
Depreciation and amortization	43,676	40,434	33,191
Impairment of gas gathering and processing systems (Note 2)	26,966	7,068	0
General and administrative	35,345	42,023	38,323
(Gain) loss on disposition of assets	7,229	(8,953)	(17,076)
Total expenses	2,512,967	1,362,711	1,026,817
Income (loss) from operations	(1,658,736)	210,233	325,033
Other income (expense):
Interest, net	(31,963)	(17,371)	(15,015)
Gain (loss) on derivatives not designated as hedges and hedge ineffectiveness, net	26,345	30,147	(8,374)
Other	45	(70)	(175)
Total other income (expense)	(5,573)	12,706	(23,564)
Income (loss) before income taxes	(1,664,309)	222,939	301,469
Income tax expense (benefit):
Current	(20,616)	9,378	15,991
Deferred	(606,332)	77,285	100,732
Income tax expense (benefit)	(626,948)	86,663	116,723
Net income (loss)	$ (1,037,361)	$ 136,276	$ 184,746
Net income (loss) per common share:
Basic	$ (21.12)	$ 2.80	$ 3.83
Diluted	$ (21.12)	$ 2.78	$ 3.80