Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (7,460)	$ (6,974)
Other comprehensive loss
Unrealized loss on marketable securities, net of tax expense of $0 for each of the three months ended March 31, 2017 and 2016	(91)	(90)
Other comprehensive loss	(91)	(90)
Total comprehensive loss	$ (7,551)	$ (7,064)

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
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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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 before tax of other comprehensive income (loss) attributable to parent entity.

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Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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