Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Operating activities:
Consolidated net income	$ 341	$ 4,169
Adjustments to reconcile consolidated net income to net cash provided by operating activities:
Depreciation and amortization	2,632	2,628
Stock compensation expense	318	384
Excess tax benefit of share-based compensation	(51)	(12)
Decrease in long-term deferred revenue	(36)	(35)
Decrease in long-term income taxes payable	(27)	17
Gain on disposal of equipment	(24)	(1)
Deferred income taxes	15	71
Credit gain on available for sale securities	(3)	(7)
Change in current assets and liabilities, net	4,359	2,692
Net cash provided by operating activities	7,524	9,906
Investing activities:
Additions to property, plant and equipment	(1,261)	(2,973)
Sales and maturities of investments	270	280
Purchases of investments	(180)	(90)
Proceeds from sale of equipment	24
Decrease (increase) in other assets	25	(5)
Net cash used in investing activities	(1,122)	(2,788)
Financing activities:
Excess tax benefit of share-based compensation	51	12
Proceeds from issuance of Common Stock	8	33
Net cash provided by financing activities	59	45
Effect of foreign exchange rates on cash	(119)	(42)
Net increase in cash and cash equivalents	6,342	7,121
Cash and cash equivalents at beginning of period	71,908	49,279
Cash and cash equivalents at end of period	$ 78,250	$ 56,400

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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).