CONDENSED CONSOLIDATED BALANCE SHEET - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 367,134	$ 10,759	$ 162,128	$ 74,488
Accounts receivable	42,185	48,031
Fair value of derivative contracts	30,222	38,576
Current income tax receivable	46,174	46,174
Inventory	535	535
Other current assets	6,531	6,346
Total current assets	492,781	150,421
Oil and gas properties, full cost method of accounting:
Proved	9,481,859	9,375,898
Less: accumulated depreciation, depletion and amortization	(8,796,412)	(8,603,955)
Net proved oil and gas properties	685,447	771,943
Unevaluated	421,429	440,043
Other property and equipment, net	28,667	29,289
Other assets, net	18,257	18,473
Total assets	1,646,581	1,410,169
Current liabilities:
Accounts payable to vendors	38,200	82,207
Undistributed oil and gas proceeds	3,875	5,992
Accrued interest	22,901	9,022
Asset retirement obligations	23,465	21,291
Current portion of long-term debt	459,201	0
Other current liabilities	32,671	40,712
Total current liabilities	580,313	159,224
Long-term debt	1,063,090	1,060,955
Asset retirement obligations	209,848	204,575
Other long-term liabilities	18,329	25,204
Total liabilities	$ 1,871,580	$ 1,449,958
Commitments and contingencies
Stockholders’ equity:
Common stock, $.01 par value; authorized 150,000,000 shares; issued 55,806,817 and 55,302,325 shares, respectively	$ 558	$ 553
Treasury stock (16,582 shares, at cost)	(860)	(860)
Additional paid-in capital	1,650,969	1,648,189
Accumulated deficit	(1,894,407)	(1,705,623)
Accumulated other comprehensive income	18,741	17,952	$ 70,800	$ 83,300
Total stockholders’ equity	(224,999)	(39,789)
Total liabilities and stockholders’ equity	$ 1,646,581	$ 1,410,169