Consolidated Balance Sheet (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 38,451	$ 106,956
Restricted cash	0	5,500
Accounts receivable	118,139	88,529
Fair value of hedging contracts	25,177	12,955
Current income tax receivable	19,946	0
Deferred taxes	26,072	27,274
Inventory	4,643	6,465
Other current assets	791	768
Total current assets	233,219	248,447
Oil and gas properties, full cost method of accounting:
Proved	6,648,168	5,789,578
Less: accumulated depreciation, depletion and amortization	(5,174,729)	(4,804,949)
Net proved oil and gas properties	1,473,439	984,629
Unevaluated	401,609	413,180
Other property and equipment, net of accumulated depreciation of $24263, and $22,467, respectively	11,172	10,722
Fair value of hedging contracts	22,543	0
Other assets, net of accumulated depreciation and amortization of $5,911 and $11,277, respectively	23,769	22,112
Total assets	2,165,751	1,679,090
Current liabilities:
Accounts payable to vendors	102,946	103,208
Undistributed oil and gas proceeds	27,328	10,037
Accrued interest	14,059	14,062
Fair value of hedging contracts	11,122	32,144
Asset retirement obligations	62,676	42,300
Current income tax payable	0	239
Other current liabilities	28,370	16,075
Total current liabilities	246,501	218,065
Long-term debt	620,000	575,000
Deferred taxes	247,835	99,227
Asset retirement obligations	363,103	331,620
Fair value of hedging contracts	815	3,606
Other long-term liabilities	19,668	21,215
Total liabilities	1,497,922	1,248,733
Commitments and contingencies
Stockholders' equity:
Common stock, $.01 par value; authorized 100,000,000 shares; issued 48,076,860 and 47,764,505 shares, respectively	481	478
Treasury stock (16,582 shares, respectively, at cost)	(860)	(860)
Additional paid-in capital	1,338,565	1,331,500
Accumulated deficit	(692,225)	(886,557)
Accumulated other comprehensive income (loss)	21,868	(14,204)
Total stockholders' equity	667,829	430,357
Total liabilities and stockholders' equity	$ 2,165,751	$ 1,679,090