Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenues:
Oil and gas sales	$ 602,341	$ 436,632	$ 371,749
Price-risk management and other, net	(3,210)	1,797	(1,304)
Total Revenues	599,131	438,429	370,445
Costs and Expenses:
General and administrative, net	45,362	36,359	34,046
Depreciation, depletion, and amortization	221,230	162,572	166,108
Accretion of asset retirement obligation	4,570	3,956	2,906
Lease operating cost	104,791	81,929	76,740
Severance and other taxes	52,508	45,868	41,326
Interest expense, net	35,566	33,437	30,663
Debt retirement cost			3,961
Write-down of oil and gas properties			79,312
Total Costs and Expenses	464,027	364,121	435,062
Income (Loss) from Continuing Operations Before Income Taxes	135,104	74,308	(64,617)
Provision (Benefit) for Income Taxes	50,494	27,833	(25,541)
Income (Loss) from Continuing Operations	84,610	46,475	(39,076)
Income (Loss) from Discontinued Operations, net of taxes	14,211	(181)	(254)
Net Income (Loss)	$ 98,821	$ 46,294	$ (39,330)
Per Share Amounts-
Basic: Income (Loss) from Continuing Operations	$ 1.96	$ 1.19	$ (1.16)
Gain (Loss) from Discontinued Operations, net of taxes	$ 0.33	$ 0.00	$ (0.01)
Net Income (Loss)	$ 2.29	$ 1.19	$ (1.17)
Diluted: Income (Loss) from Continuing Operations	$ 1.95	$ 1.18	$ (1.16)
Gain (Loss) from Discontinued Operations, net of taxes	$ 0.33	$ 0.00	$ (0.01)
Net Income (Loss)	$ 2.27	$ 1.18	$ (1.17)
Weighted Average Shares Outstanding	42,394	38,300	33,594