CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income	$ 18,638	$ 20,069
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion of discount on available-for-sale debt securities	(40)	(38)
Amortization of deferred offering costs	155	147
Depreciation, depletion and amortization	20,582	15,531
Change in fair value of derivative financial instruments	(10,037)	(5,957)
Stock option expense	1,151	1,925
Deferred tax benefit	(76)	(68)
Change in assets and liabilities:
Increase in accounts receivable-trade	(588)	(406)
(Increase) decrease in other assets	2	(9)
Increase in accounts payable and accruals	2,690	3,167
Decrease in other long-term liabilities	(292)	(565)
Net cash provided by operating activities	32,185	33,796
Cash flows from investing activities:
Purchase, exploration and development of oil and gas properties	(28,918)	(22,420)
Purchase of property and equipment	(6,733)	(3,556)
Net cash used in investing activities	(35,651)	(25,976)
Cash flows from financing activities:
Payments on long-term debt	(2,205)	(7,728)
Issuance of common stock, net	123	97
Repurchase of preferred stock, net		(1,051)
Net cash used in financing activities	(2,082)	(8,682)
Net decrease in cash and cash equivalents	(5,548)	(862)
Cash and cash equivalents at beginning of period	11,092	17,238
Cash and cash equivalents at end of period	5,544	16,376
Supplemental disclosure of cash flow information
Cash paid for interest, net of amounts capitalized	1,948	2,454
Noncash investing and financing activities
Note payable on purchase of property and equipment		3,500
Accrued preferred stock dividend	$ 8	$ 16