CONDENSED CONSOLIDATED BALANCE SHEET (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013		Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 202,761		$ 331,224		$ 261,353	$ 279,526
Accounts receivable	190,573		171,971
Fair value of hedging contracts	745		4,549
Current income tax receivable	7,366		7,366
Deferred taxes	36,098	[1]	31,710	[1]
Inventory	4,651		3,723
Other current assets	1,774		1,874
Total current assets	443,968		552,417
Oil and gas properties, full cost method of accounting:
Proved	7,898,668		7,804,117
Less: accumulated depreciation, depletion and amortization	(6,052,894)		(5,908,760)
Net proved oil and gas properties	1,845,774		1,895,357
Unevaluated	906,043		724,339
Other property and equipment, net	26,975		26,178
Fair value of hedging contracts	1,867		1,378
Other assets, net	37,154		48,887
Total assets	3,261,781		3,248,556
Current liabilities:
Accounts payable to vendors	165,973		195,677
Undistributed oil and gas proceeds	55,676		37,029
Accrued interest	22,247		9,022
Fair value of hedging contracts	15,277		7,753
Asset retirement obligations	87,927		67,161
Other current liabilities	28,467		54,520
Total current liabilities	375,567		371,162
Long-term debt	1,030,466		1,027,084
Deferred taxes	406,477	[1]	390,693	[1]
Asset retirement obligations	416,171		435,352
Fair value of hedging contracts	376		470
Other long-term liabilities	46,772		53,509
Total liabilities	2,275,829		2,278,270
Commitments and contingencies
Stockholders' equity:
Common stock, $.01 par value; authorized 100,000,000 shares; issued 49,083,039 and 48,750,533 shares, respectively	491		488
Treasury stock (16,582 shares, at cost)	(860)		(860)
Additional paid-in capital	1,394,694		1,397,885
Accumulated deficit	(399,222)		(425,165)
Accumulated other comprehensive loss	(9,151)		(2,062)
Total stockholders' equity	985,952		970,286
Total liabilities and stockholders' equity	$ 3,261,781		$ 3,248,556

[1] Deferred income taxes have been allocated to the Guarantor Subsidiary where related oil and gas properties reside.