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Additional Paid-In Capital (Narrative) (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Warrants outstanding (in shares) | 19,977,743 | 19,977,743 | 19,977,743
Unrecognized compensation expense related to unvested options | $ 24 |  |
Weighted average compensation recognition period | 2 months 19 days |  |
Number of awards cancelled | 351,340 |  |
In December 2014 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of warrants expected to expire in future (in shares) | 2,091,275 |  |
Stock Option Plan [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Percentage of common shares reserved for issuance | 10.00% |  |
Weighted average compensation recognition period | 2 months 19 days |  |
2012 Offering [Member] | In October 2015 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of warrants expected to expire in future (in shares) | 15,219,802 |  |
2012 Offering [Member] | In July 2014 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of warrants expected to expire in future (in shares) | 2,666,666 |  |
Restricted Stock Units (RSUs) [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unrecognized compensation expense related to unvested options | $ 2,932 |  |
Weighted average compensation recognition period | 1 year 11 months 16 days |  |

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- Definition Number of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph i -Article 4 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Number of shares under non-option equity instrument agreements for which rights to exercise are expected to expire in the future. + References No definition available. + Details
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