Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenues:
Oil and gas sales	$ 146,477	$ 136,142
Price-risk management and other, net	(240)	(264)
Total Revenues	146,237	135,878
Costs and Expenses:
General and administrative, net	12,725	11,883
Depreciation, depletion, and amortization	60,120	61,363
Accretion of asset retirement obligation	1,775	1,112
Lease operating cost	27,424	24,619
Transportation and gas processing	6,030	4,594
Severance and other taxes	9,775	12,960
Interest expense, net	16,802	13,465
Total Costs and Expenses	134,651	129,996
Income Before Income Taxes	11,586	5,882
Provision for Income Taxes	4,377	2,312
Net Income	$ 7,209	$ 3,570
Per Share Amounts-
Earnings Per Share (Basic)	$ 0.16	$ 0.08
Earnings Per Share (Diluted)	$ 0.16	$ 0.08
Weighted Average Shares Outstanding - Basic	43,167	42,674
Weighted Average Shares Outstanding - Diluted	43,323	42,874