Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities:
Consolidated net loss	$ (14,070)us-gaap_ProfitLoss	$ (23,504)us-gaap_ProfitLoss	$ (3,798)us-gaap_ProfitLoss
Adjustments to reconcile consolidated net loss to net cash provided by (used for) operating activities:
Depreciation and amortization	9,805	10,008	10,423
Stock-based compensation expense	1,634	2,450	1,244
Provision for doubtful accounts	66us-gaap_ProvisionForDoubtfulAccounts
Deferred income taxes	18us-gaap_DeferredIncomeTaxExpenseBenefit	4,491us-gaap_DeferredIncomeTaxExpenseBenefit	(369)us-gaap_DeferredIncomeTaxExpenseBenefit
Impairment of goodwill			2,012us-gaap_GoodwillImpairmentLoss
Decrease in long-term deferred revenue	(139)	(139)	(139)
(Decrease) increase in long-term income taxes payable	(472)	(155)	135
Excess tax benefit of share-based compensation			(105)
Gain on disposal of equipment	(22)	(26)	(33)
Credit (gain) loss on available for sale securities	(311)	78	9
Change in current assets and liabilities, net	5,682	2,107	7,859
Net cash provided by (used for) operating activities	2,191	(4,690)	17,238
Investing activities:
Purchases of investments	(340)		(270)
Sales and maturities of investments	3,460	1,024	3,630
Additions to property, plant and equipment	(7,128)	(6,179)	(7,396)
Proceeds from sale of equipment	22	26	33
(Increase) decrease in other assets	(43)	49	(81)
Net cash used for investing activities	(4,029)	(5,080)	(4,084)
Financing activities:
Purchases of Common Stock		(17,100)
Proceeds from issuance of Common Stock	788	27	9
Noncontrolling interest dividends paid	(162)	(531)	(378)
Excess (reversal of) tax benefit of share-based compensation		(451)	105
Net cash provided by (used for) financing activities	626	(18,055)	(264)
Effect of foreign exchange rates on cash	60	(390)	(244)
Net (decrease) increase in cash and cash equivalents	(1,152)	(28,215)	12,646
Cash and cash equivalents at beginning of period	56,339	84,554	71,908
Cash and cash equivalents at end of period	55,187	56,339	84,554
Change in assets and liabilities:
Accounts receivable	(1,151)	(821)	4,052
Inventories, net	3,202us-gaap_IncreaseDecreaseInInventories	33us-gaap_IncreaseDecreaseInInventories	5,591us-gaap_IncreaseDecreaseInInventories
Other current assets	1,029	(1,647)	380
Accounts payable and accrued liabilities	300	4,580	(1,670)
Accrued severance charges	1,855	49
Income taxes payable	26	(321)	(84)
Deferred revenue	421	234	(410)
Change in current assets and liabilities, net	5,682	2,107	7,859
Supplemental disclosures:
Cash paid during the year for income taxes, net of refunds	$ (1,529)us-gaap_IncomeTaxesPaidNet	$ (61)us-gaap_IncomeTaxesPaidNet	$ 975us-gaap_IncomeTaxesPaidNet

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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.