Consolidated Statements of Comprehensive Loss (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Consolidated Statement of Comprehensive Loss:
Net loss	$ (19,643)us-gaap_NetIncomeLoss	$ (24,281)us-gaap_NetIncomeLoss
Other comprehensive income:
Net change in unrealized gain on available-for-sale marketable securities	42	1
Reclassification adjustments for net realized gains on available-for-sale marketable securities	0	0
Other comprehensive income	42	1
Comprehensive loss	$ (19,601)us-gaap_ComprehensiveIncomeNetOfTax	$ (24,280)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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