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Net Loss Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 3 Months Ended | 12 Months Ended | 24 Months Ended | 147 Months Ended
--- | --- | --- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Dec. 31, 2008 | Dec. 31, 2007 | Dec. 31, 2006 | Dec. 31, 2005 | Dec. 31, 2004 | Dec. 31, 2003 | Mar. 31, 2014
Summary of basic and diluted loss per share |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss | $ (2,389) | $ (1,071) | $ (6,939) | $ (4,320) | $ (5,364) | $ (8,420) | $ (9,138) | $ (19,431) | $ (13,994) | $ (5,241) | $ (1,459) | $ (511) | $ (116) | $ (77,322)
Net loss available to common shareholders | $ (2,389) | $ (1,071) |  |  |  |  |  |  |  |  |  |  |  | $ (80,374)
Weighted average shares of common stock outstanding | 18,785,418 | 3,037,546 |  |  |  |  |  |  |  |  |  |  |  |
Less: Weighted-average shares of unvested common stock |  | (2,783) |  |  |  |  |  |  |  |  |  |  |  |
Total weighted-average shares used in computing net loss per share attributed to common stockholders | 18,785,418 | 3,034,763 |  |  |  |  |  |  |  |  |  |  |  |
Basic and diluted loss per share | $ (0.13) | $ (0.35) |  |  |  |  |  |  |  |  |  |  |  |

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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References No definition available. + Details
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=6519514 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=6518256 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.19) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.18) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.22) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e565-108580 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 + Details
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