Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Operating activities:
Consolidated net income (loss)	$ 3,442us-gaap_ProfitLoss	$ (5,426)us-gaap_ProfitLoss
Adjustments to reconcile consolidated net income (loss) to net cash provided by (used for) operating activities:
Depreciation and amortization	2,403	2,443
Stock-based compensation expense	563	234
Provision for doubtful accounts	33us-gaap_ProvisionForDoubtfulAccounts	53us-gaap_ProvisionForDoubtfulAccounts
Decrease in long-term deferred revenue	(34)	(34)
Gain on disposal of equipment	(35)	(4)
Credit gain on available-for-sale securities	(4)
Increase (decrease) in long-term income taxes payable	6	(2)
Change in current assets and liabilities, net	(1,304)	(1,744)
Net cash provided by (used for) operating activities	5,070	(4,480)
Investing activities:
Additions to property, plant and equipment	(1,469)	(1,554)
Sales and maturities of investments	270
Proceeds from sale of equipment	35	4
Increase in other assets	(65)	(34)
Net cash used for investing activities	(1,229)	(1,584)
Financing activities:
Proceeds from issuance of Common Stock	310	5
Net cash provided by financing activities	310	5
Effect of foreign exchange rates on cash	(16)	27
Net increase (decrease) in cash and cash equivalents	4,135	(6,032)
Cash and cash equivalents at beginning of period	55,187	56,339
Cash and cash equivalents at end of period	$ 59,322	$ 50,307

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.