Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating activities
Net loss	$ (12,073)	$ (14,249)
Adjustments to reconcile net loss to net cash provided by operating activities
Unrealized loss (gain) on derivatives	1,149	(1,534)
Depletion, depreciation and amortization	52,799	22,578
Accretion of asset retirement obligations	170	158
Full-cost ceiling impairment	36,801	35,673
Stock option and grant expense	(585)	1,379
Restricted stock and restricted stock units expense	391	36
Deferred income tax benefit	(1,430)	(6,906)
Loss on asset sales and inventory impairment	60
Changes in operating assets and liabilities
Accounts receivable	(8,718)	(2,411)
Lease and well equipment inventory	(285)	(1)
Prepaid expenses	179	240
Other assets	(650)
Accounts payable, accrued liabilities and other liabilities	6,105	(2,360)
Income taxes payable	188
Royalties payable	4,065	2,548
Advances from joint interest owners	1,782	(723)
Other long-term liabilities	406	15
Net cash provided by operating activities	80,325	34,443
Investing activities
Oil and natural gas properties capital expenditures	(212,702)	(104,733)
Expenditures for other property and equipment	(5,297)	(3,303)
Purchases of certificates of deposit	(416)	(3,721)
Maturities of certificates of deposit	1,485	3,985
Net cash used in investing activities	(216,930)	(107,772)
Financing activities
Repayments of borrowings under Credit Agreement	(123,000)
Borrowings under Credit Agreement	116,000	60,000
Proceeds from issuance of common stock	146,510	592
Swing sale profit contribution	24
Cost to issue equity	(11,599)	(1,185)
Proceeds from stock options exercised	2,660	837
Payment of dividends - Class B	(96)	(206)
Net cash provided by financing activities	130,499	60,038
Decrease in cash and cash equivalents	(6,106)	(13,291)
Cash and cash equivalents at beginning of period	10,284	21,059
Cash and cash equivalents at end of period	$ 4,178	$ 7,768