Consolidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (2,585)us-gaap_NetIncomeLoss	$ (2,603)us-gaap_NetIncomeLoss
Other comprehensive (loss) / income:
Amounts reclassified for net realized (gains) / losses on available-for-sale securities included in net loss	(1)	491
Net unrealized gains / (losses) on available-for-sale securities occurring during the period	22	(38)
Other comprehensive income	21	453
Total comprehensive loss	$ (2,564)us-gaap_ComprehensiveIncomeNetOfTax	$ (2,150)us-gaap_ComprehensiveIncomeNetOfTax

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 of other comprehensive income (loss) attributable to parent entity.

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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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