UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
CASH PROVIDED BY OPERATIONS:
Net earnings	$ 6,575	$ 5,583
Adjustments to reconcile net earnings to net cash from operating activities-
Depreciation, depletion and amortization	4,163	3,422
Property sale (gains) losses	(2,901)	(2,883)
Dry hole costs incurred	11	362
Impairment of oil and natural gas properties	265	226
Provision for doubtful accounts	(49)	300
Deferred income taxes	(27)	2,597
Net change in fair value contracts	2,882	(814)
Decrease (increase) in accounts receivable	(18,930)	(31,878)
Decrease (increase) in inventories	(10,507)	(4,165)
Decrease (increase) in income tax receivable	417	58
Decrease (increase) in prepayments	3,218	559
Increase (decrease) in accounts payable	19,102	26,342
Increase (decrease) in accrued liabilities	4,931	1,186
Other, net	61	(177)
Net cash provided by operating activities	9,211	718
INVESTING ACTIVITIES:
Property and equipment additions	(15,222)	(14,976)
Insurance and state collateral (deposits) refunds	42	0
Proceeds from property sales	1,346	6,609
Proceeds from discontinued operations	3,546	0
Investment in marketable securities	0	(11,098)
Redemption of marketable securities	0	2,400
Net cash (used in) investing activities	(10,288)	(17,065)
Increase (decrease) in cash and cash equivalents	(1,077)	(16,347)
Cash and cash equivalents at beginning of period	37,066	29,032
Cash and cash equivalents at end of period	$ 35,989	$ 12,685

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).