Conslidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net loss	$ (8,705)us-gaap_NetIncomeLoss	$ (13,504)us-gaap_NetIncomeLoss	$ (18,735)us-gaap_NetIncomeLoss
Unrealized gains (loss) on securities:
Unrealized holding (loss) gain arising during period	(71)	3	107
Reclassification for recognized gain on marketable investment securities during the period	12	4	4
Net unrealized gain (loss) on marketable investment securities	(59)	7	111
Foreign currency translation gain (loss)	(2,270)	44	(10)
Other comprehensive (loss) income	(2,329)	51	101
Comprehensive loss	$ (11,034)us-gaap_ComprehensiveIncomeNetOfTax	$ (13,453)us-gaap_ComprehensiveIncomeNetOfTax	$ (18,634)us-gaap_ComprehensiveIncomeNetOfTax

No authoritative reference available.

No definition available.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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