Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]
OIL AND GAS REVENUES	$ 520,182	$ 368,180	$ 202,167
COSTS AND EXPENSES
Lease operating	46,828	31,471	28,314
Production tax	19,811	13,542	5,697
Ad valorem tax	8,701	9,813	3,625
Depreciation, depletion and amortization	213,820	165,621	84,606
General and administrative (inclusive of stock-based compensation expense of $29,373, $11,689 and $11,864 for the years ended December 31, 2013, 2012 and 2011, respectively)	77,492	48,708	41,539
Accretion related to asset retirement obligations	471	372	235
Loss on sale of oil and gas properties	45,377	0	0
TOTAL COSTS AND EXPENSES	412,500	269,527	164,016
OPERATING INCOME	107,682	98,653	38,151
OTHER INCOME AND EXPENSES
Gain (loss) on derivative instruments, net	(18,417)	31,371	48,423
Interest expense	(84,578)	(73,006)	(50,998)
Capitalized interest	29,889	24,848	23,369
Other income (expense), net	185	267	(800)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	34,761	82,133	58,145
INCOME TAX EXPENSE	(12,903)	(30,956)	(25,611)
NET INCOME FROM CONTINUING OPERATIONS	21,858	51,177	32,534
NET INCOME FROM DISCONTINUED OPERATIONS, NET OF INCOME TAXES	21,825	4,310	4,095
NET INCOME	$ 43,683	$ 55,487	$ 36,629
NET INCOME PER COMMON SHARE - BASIC
Net income from continued operations (in dollars per share)	$ 0.54	$ 1.29	$ 0.83
Net income (loss) from discontinued operations (in dollars per share)	$ 0.53	$ 0.11	$ 0.11
Net income per share basic (in dollars per share)	$ 1.07	$ 1.40	$ 0.94
NET INCOME PER COMMON SHARE - DILUTED
Net income from continuing operations (in dollars per share)	$ 0.53	$ 1.28	$ 0.82
Net income (loss) from discontinued operations (in dollars per share)	$ 0.53	$ 0.11	$ 0.10
Net income per share, diluted (in dollars per share)	$ 1.06	$ 1.39	$ 0.92
WEIGHTED AVERAGE COMMON SHARES OUTSTANDING
Basic (in shares)	40,781	39,591	39,077
Diluted (in shares)	41,355	40,026	39,668