Consolidated Statements Of Operations (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenues:
Oil and natural gas sales	$ 530,041	$ 408,561	$ 292,387
Gain (loss) from oil and natural gas hedging activities	(27,452)	(29,393)	19,403
Other revenues	4,070	4,127	2,864
Total revenues	506,659	383,295	314,654
Costs and expenses:
Lease operating	121,420	106,127	94,070
Production tax	34,321	26,495	20,341
Depreciation, depletion and amortization	146,083	109,503	104,193
Loss on impairment of oil and natural gas properties	0	0	240,790
Loss on impairment of other assets	0	4,150	0
General and administrative	42,056	29,915	23,741
Litigation settlement	0	0	2,928
Other expenses	3,448	3,148	1,957
Total costs and expenses	347,328	279,338	488,020
Operating income (loss)	159,331	103,957	(173,366)
Non-operating income (expense):
Interest expense	(96,720)	(81,370)	(90,102)
Non-hedge derivative gains	34,408	38,595	11,169
Loss on extinguishment of debt	(20,592)	(2,241)	0
Financing costs	0	(1,812)	(2,169)
Other income	1,545	387	13,921
Net non-operating expense	(81,359)	(46,441)	(67,181)
Income (loss) from continuing operations before income taxes	77,972	57,516	(240,547)
Income tax expense (benefit)	35,924	23,803	(89,777)
Income (loss) from continuing operations	42,048	33,713	(150,770)
Income from discontinued operations, net of related taxes	0	0	6,452
Net income (loss)	$ 42,048	$ 33,713	$ (144,318)