CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 8,210	$ 2,829
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion of discount on available-for-sale debt securities	(16)	(15)
Amortization of deferred offering costs	56	52
Depreciation, depletion and amortization	10,354	11,570
Change in fair value of derivative financial instruments	(807)	1,466
Stock option expense	532	315
Deferred tax expense (benefit)	(8)	7
Change in assets and liabilities:
Decrease (increase) in accounts receivable-trade	8,413	(1,537)
Increase in other assets	(2,228)	(57)
Increase (decrease) in accounts payable and accruals	(8,817)	2,142
Decrease in other long-term liabilities	(198)	(751)
Net cash provided by operating activities	15,491	16,021
Cash flows from investing activities:
Purchase, exploration and development of oil and gas properties	(10,902)	(2,824)
Purchase of property and equipment	(446)	(1,118)
Net cash used in investing activities	(11,348)	(3,942)
Cash flows from financing activities:
Payments on debt and debentures	(14,000)	(10,000)
Proceeds from the exercise of stock options	71	191
Net cash used in financing activities	(13,929)	(9,809)
Net (decrease) increase in cash and cash equivalents	(9,786)	2,270
Cash and cash equivalents at beginning of period	11,620	8,475
Cash and cash equivalents at end of period	1,834	10,745
Supplemental disclosure of cash flow information
Cash paid for interest, net of amounts capitalized	711	668
Noncash investing and financing activities
Accrued preferred stock dividend	$ 3	$ 3