Consolidated Statements Of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]
Crude oil revenues	$ 173,277	$ 117,797	$ 469,601	$ 311,084
Natural gas liquids revenues	7,798	6,025	19,669	11,532
Natural gas revenues	15,150	20,507	57,642	67,838
Total revenues	196,225	144,329	546,912	390,454
Costs and Expenses
Lease operating	21,019	12,934	51,002	34,926
Production taxes	8,393	5,590	22,666	14,687
Ad valorem taxes	2,235	2,125	5,569	6,848
Depreciation, depletion and amortization	83,572	55,362	228,912	151,587
General and administrative	9,538	19,715	65,481	53,722
Loss on derivative instruments, net	(71,783)	27,658	(11,153)	16,486
Interest expense, net	12,201	13,402	36,557	42,367
Other (income) expense, net	549	(28)	1,536	(95)
Total Costs and Expenses	65,724	136,758	400,570	320,528
Income From Continuing Operations Before Income Taxes	130,501	7,571	146,342	69,926
Income tax expense	(47,504)	(1,859)	(53,510)	(25,853)
Income From Continuing Operations	82,997	5,712	92,832	44,073
Income (Loss) From Discontinued Operations, Net of Income Taxes	792	(1,191)	(748)	23,599
Net Income (loss)	$ 83,789	$ 4,521	$ 92,084	$ 67,672
Net Income (Loss) Per Common Share - Basic
Net income from continuing operations - basic (in dollars per share)	$ 1.83	$ 0.14	$ 2.05	$ 1.10
Net income from discontinued operations - basic (in dollars per share)	$ 0.02	$ (0.03)	$ (0.02)	$ 0.59
Net income per share, basic (in dollars per share)	$ 1.85	$ 0.11	$ 2.03	$ 1.69
Net Income (Loss) Per Common Share - Diluted
Net income from continuing operations - diluted (in dollars per share)	$ 1.80	$ 0.14	$ 2.01	$ 1.09
Net income from discontinued operations - diluted (in dollars per share)	$ 0.02	$ (0.03)	$ (0.01)	$ 0.58
Net income per share, diluted (in dollars per share)	$ 1.82	$ 0.11	$ 2.00	$ 1.67
Weighted Average Common Shares Outstanding
Basic (in shares)	45,257	40,386	45,277	40,083
Diluted (in shares)	46,029	40,927	46,109	40,601