CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities
Net loss	$ (16,383)	$ (11,899)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion and amortization	51,576	50,817
Derivative contracts:
Net losses	7,761	305
Cash settlements	3,557	7,981
Deferred income tax benefit	(8,789)	(6,601)
Loss (gain) on sales of assets, net	549	(756)
Non-cash exploration expense	5,262	8,171
Non-cash interest expense	946	1,015
Share-based compensation (equity-classified)	1,085	1,615
Other, net	288	56
Changes in operating assets and liabilities	(237)	19,997
Net cash provided by operating activities	45,615	70,701
Cash flows from investing activities
Capital expenditures - property and equipment	(85,973)	(94,469)
Proceeds from sales of assets, net	878	778
Net cash used in investing activities	(85,095)	(93,691)
Cash flows from financing activities
Proceeds from revolving credit facility borrowings	38,000	23,000
Repayment of revolving credit facility borrowings	0	(3,000)
Dividends paid on preferred stock	(1,687)	0
Dividends paid on common stock	0	(2,586)
Other, net	(61)	0
Net cash provided by financing activities	36,252	17,414
Net decrease in cash and cash equivalents	(3,228)	(5,576)
Cash and cash equivalents - beginning of period	17,650	7,512
Cash and cash equivalents - end of period	14,422	1,936
Cash paid for:
Interest (net of amounts capitalized)	340	557
Income taxes (net of refunds received)	$ 0	$ (301)