Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 92	$ 846
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	410	643
Provision for doubtful accounts	(48)
Deferred taxes		255
Foreign currency transaction (gains) losses	10	(80)
Stock compensation costs	105	106
Changes in operating assets and liabilities:
Accounts receivable	1,623	260
Inventories	(1,438)	(359)
Income tax refunds receivable	9	(19)
Other assets	(91)	138
Accounts payable	970	(872)
Advance customer payments	(58)	(298)
Accrued expenses	(379)	(160)
Net cash provided by operating activities	1,205	460
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from maturities of available-for-sale marketable securities	2,592	3,735
Proceeds from sales of available-for-sale marketable securities	1,350	1,048
Purchases of available-for-sale marketable securities	(8,638)	(4,040)
Additions to equipment and leasehold improvements	(412)	(76)
Additions to patents	(25)	(29)
Net cash provided by (used in) investing activities	(5,133)	638
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of stock options
Net cash provided by financing activities
Effects of exchange rate changes on cash and cash equivalents	77	24
Net increase (decrease) in cash and cash equivalents	(3,851)	1,122
Cash and cash equivalents - beginning of period	13,791	8,427
Cash and cash equivalents - end of period	$ 9,940	$ 9,549

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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).