CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:
Net income	$ 18,964	$ 12,013
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion of discount on available-for-sale debt securities	(32)	(30)
Amortization of deferred offering costs	113	106
Depreciation, depletion and amortization	20,889	23,381
Change in fair value of derivative financial instruments	(617)	(2,156)
Stock option expense	1,069	945
Deferred tax (benefit) expense	(14)	39
Change in assets and liabilities:
Decrease (increase) in accounts receivable-trade	6,767	(1,489)
Increase in other assets	(510)	(869)
(Decrease) increase in accounts payable and accruals	(7,018)	1,666
Decrease in other long-term liabilities	(260)	(1,194)
Net cash provided by operating activities	39,351	32,412
Cash flows from investing activities:
Purchase, exploration and development of oil and gas properties	(35,312)	(22,113)
Purchase of property and equipment	(982)	(1,766)
Net cash used in investing activities	(36,294)	(23,879)
Cash flows from financing activities:
Proceeds from line of credit	14,500
Payments on debt and debentures	(27,525)	(10,017)
Proceeds from the exercise of stock options	102	361
Net cash used in financing activities	(12,923)	(9,656)
Net decrease in cash and cash equivalents	(9,866)	(1,123)
Cash and cash equivalents at beginning of period	11,620	8,475
Cash and cash equivalents at end of period	1,754	7,352
Supplemental disclosure of cash flow information
Cash paid for interest, net of amounts capitalized	1,335	1,347
Noncash investing and financing activities
Accrued preferred stock dividend	$ 5	$ 5