CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$ 26,672	$ 11,477
Adjustments to reconcile net income to net cash provided by operating activities:
Accretion of discount on available-for-sale debt securities	(45)	(43)
Amortization of deferred offering costs	160	153
Depreciation, depletion and amortization	34,368	34,571
Change in fair value of derivative financial instruments	(905)	1,315
Gain on sale of US treasury bonds - available for sale		(4)
Stock option expense	1,492	1,689
Deferred tax expense (benefit)	45	(14)
Change in assets and liabilities:
Increase in accounts receivable-trade	(3,989)	(2,947)
(Increase) decrease in other assets	(723)	255
Increase in accounts payable and accruals	2,680	7,237
Decrease in other long-term liabilities	(1,648)	(1,052)
Net cash provided by operating activities	58,107	52,637
Cash flows from investing activities:
Purchase, exploration and development of oil and gas properties	(50,053)	(54,952)
Funds held in escrow		(3,239)
Purchase of property and equipment	(2,019)	(1,587)
Proceeds from US treasury bonds - available for sale		13
Net cash used in investing activities	(52,072)	(59,765)
Cash flows from financing activities:
Proceeds from line of credit	5,000	10,000
Payments on debt and debentures	(10,017)	(118)
Proceeds from the exercise of stock options	597	107
Net cash (used in) provided by financing activities	(4,420)	9,989
Net increase in cash and cash equivalents	1,615	2,861
Cash and cash equivalents at beginning of period	8,475	10,614
Cash and cash equivalents at end of period	10,090	13,475
Supplemental disclosure of cash flow information
Cash paid for interest, net of amounts capitalized	2,122	2,339
Noncash investing and financing activities
Accrued preferred stock dividend	$ 8	$ 8