Consolidated Statements Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements Comprehensive Loss
Net Loss	$ (36,060)	$ (32,630)	$ (21,884)
Other comprehensive loss:
Unrealized loss on available-for-sale securities	(4)
Total other comprehensive loss:	(4)
Comprehensive loss	$ (36,064)	$ (32,630)	$ (21,884)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

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

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