Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues
Oil, natural gas liquids and natural gas	$ 462,363	$ 354,223	$ 177,422
Other	2,360	755	24
Total revenues	464,723	354,978	177,446
Operatings expenses
Lease operating	51,262	44,620	43,649
Marketing,gathering, transportation and other	23,621	17,567	17,491
Production and ad valorem taxes	18,161	17,824	4,400
General and administrative	30,373	27,469	21,434
Depletion, depreciation and amortization	189,516	137,068	91,353
Accretion	958	952	862
Impairments	423,092	1,125	664,438
Other operating expenses (income)	25,583	(858)	516
Total operating expenses	762,566	245,767	844,143
Other income (expenses)
Interest expense, net of capitalized interest	(115,586)	(99,471)	(49,387)
Gain on derivative instruments	121,669	814	29,267
Other income	27	23	18
Total other income (expenses)	6,110	(98,634)	(20,102)
Net income (loss) before income taxes	(291,733)	10,577	(686,799)
Income tax expense	34,987
Net income (loss) including noncontrolling interests	(326,720)	10,577	(686,799)
Less: Net income (loss) applicable to noncontrolling interests			17
Net income (loss)	$ (326,720)	$ 10,577	$ (686,782)
Net income (loss) per share:
Net income (loss) per share - Basic (in dollars per share)	$ (2.67)	$ 0.09	$ (6.92)
Net income (loss) per share - Diluted (in dollars per share)	$ (2.67)	$ 0.09	$ (6.92)
Weighted average shares outstanding – basic (in shares)	122,237	118,863	99,179
Weighted average shares outstanding – diluted (in shares)	122,237	118,863	99,179