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Net Loss Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 12 Months Ended | 132 Months Ended
--- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2012
Summary of basic and diluted loss per share |  |  |
Net loss | $ (4,320) | $ (5,364) |
Net loss available to common shareholders | $ (4,320) | $ (5,364) | $ (69,020)
Weighted average shares of common stock outstanding | 2,226,299 | 1,675,824 |
Less: Weighted-average shares of unvested common stock | (2,783) | (2,783) |
Total weighted-average shares used in computing net loss per share attributed to common stockholders | 2,223,516 | 1,673,041 |
Basic and diluted loss per share | $ (1.94) | $ (3.21) |

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