Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Consolidated Statements Of Operations [Abstract]
Oil and gas production revenues	$ 170,135	$ 102,121	$ 509,518	$ 296,249
Costs, operating expenses and other:
Lease operating	27,707	27,493	101,754	89,423
Exploration	66	543	1,066	1,264
General and administrative	13,540	9,646	33,442	28,269
Depreciation, depletion and amortization	77,715	62,505	231,353	158,621
Impairment of oil and gas properties		2,988	45,704	15,078
Accretion of asset retirement obligation	3,722	3,566	11,157	10,419
Drilling interruption costs			19,691	8,714
Loss on abandonment	2,691	32	4,074	233
Gain on exchange/disposal of properties	(1,000)	(15,000)	(1,000)	(27,020)
Total operating expenses	124,441	91,773	447,241	285,001
Income from operations	45,694	10,348	62,277	11,248
Other income (expense):
Interest income	68	293	184	591
Interest expense, net	(77,356)	(69,249)	(249,883)	(146,113)
Derivative income (expense)	86,693	(12,665)	72,349	14,799
Gain (loss) on debt extinguishment			1,091	(78,171)
Total other non operating income (expenses)	9,405	(81,621)	(176,259)	(208,894)
Income (loss) before income taxes	55,099	(71,273)	(113,982)	(197,646)
Income tax benefit (expense):
Current		297		70
Deferred	(44,136)	19,575	(38,784)	76,196
Total	(44,136)	19,872	(38,784)	76,266
Net income (loss)	10,963	(51,401)	(152,766)	(121,380)
Less income attributable to the redeemable noncontrolling interest	(9,829)	(4,129)	(16,954)	(12,355)
Less convertible preferred stock dividends	(6,725)	(2,820)	(12,270)	(8,420)
Net loss attributable to common shareholders	$ (5,591)	$ (58,350)	$ (181,990)	$ (142,155)
Net loss per share attributable to common shareholders:
Basic	$ (0.11)	$ (1.15)	$ (3.56)	$ (2.81)
Diluted	$ (0.11)	$ (1.15)	$ (3.56)	$ (2.81)
Weighted average number of common shares:
Basic	51,113	50,800	51,061	50,673
Diluted	51,113	50,800	51,061	50,673