CONDENSED STATEMENTS OF COMPREHENSIVE LOSS (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONDENSED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (9,315)us-gaap_NetIncomeLoss	$ (8,440)us-gaap_NetIncomeLoss
Net unrealized gain (loss) on marketable securities	67	(76)
Comprehensive loss	$ (9,248)us-gaap_ComprehensiveIncomeNetOfTax	$ (8,516)us-gaap_ComprehensiveIncomeNetOfTax

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

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