Condensed Consolidated Balance Sheets (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Current Assets:
Cash and cash equivalents	$ 32,298	$ 86,367
Accounts receivable	50,146	46,975
Deferred tax assets	3,310	6,347
Other current assets	14,842	18,105
Assets held for sale	0	564
Total Current Assets	100,596	158,358
Property and Equipment:
Property and Equipment	4,201,003	3,951,107
Less - Accumulated depreciation, depletion, and amortization	(2,487,813)	(2,378,262)
Property and Equipment, Net	1,713,190	1,572,845
Other Long-Term Assets	12,613	12,713
Total Assets	1,826,399	1,743,916
Current Liabilities:
Accounts payable and accrued liabilities	52,212	75,594
Accrued capital costs	75,563	64,879
Accrued interest	10,760	11,010
Undistributed oil and gas revenues	4,006	5,252
Total Current Liabilities	142,541	156,735
Long-Term Debt	471,746	471,624
Deferred Income Taxes	180,484	157,565
Asset Retirement Obligation	71,574	70,171
Other Long-Term Liabilities	9,855	7,804
Commitments and Contingencies
Stockholders' Equity:
Preferred stock, $.01 par value, 5,000,000 shares authorized, none outstanding	0	0
Common stock, $.01 par value, 150,000,000 shares authorized, 42,946,570 and 42,440,583 shares issued, and 42,465,727 and 41,999,058 shares outstanding, respectively	429	424
Additional paid-in capital	717,945	706,857
Treasury stock held, at cost, 480,843 and 4441,525 shares, respectively	(12,246)	(9,778)
Retained earnings	243,861	182,652
Accumulated other comprehensive income (loss), net of income tax	210	(138)
Total Stockholders' Equity	950,199	880,017
Total Liabilities and Stockholders' Equity	$ 1,826,399	$ 1,743,916