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Common Shares (Public Offering) (Details) $ / shares in Units, $ in Thousands | 1 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Aug. 31, 2016 USD ($) item $ / shares shares | Dec. 31, 2016 USD ($) $ / shares shares | Dec. 31, 2014 $ / shares | Dec. 31, 2013 $ / shares
Subsidiary, Sale of Stock [Line Items] |  |  |  |
Number of units issued | 12,362,500 |  |  |
Proceeds from issuance of common shares | $ | $ 15,883 | $ 15,883 |  |
Number of common shares in each unit | item | 1 |  |  |
Number of common shares to purchase each warrant | 0.50 |  |  |
Over-Allotment Option |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |
Number of units issued | 1,612,500 |  |  |
Warrants |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |
Number of common shares purchased for each warrant | 1 |  |  |
Issued (in shares) | 6,514,625 | 6,514,625 |  |
Exercise price (in dollars per share) | $ / shares | $ 1.92 | $ 1.92 | $ 5.00 | $ 4.63
Period warrants are exercisable | 36 months |  |  |
Fair value of warrants | $ | $ 3,320 |  |  |
Expected volatility (as a percent) |  | 89.00% |  |
Risk-free interest rate (as a percent) |  | 0.86% |  |
Expected term (in years) |  | 3 years |  |
Share price (in dollars per share) | $ / shares | $ 1.13 |  |  |
Warrants | Over-Allotment Option |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |
Issued (in shares) | 333,375 |  |  |

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- Definition Period the instrument, asset or liability is expected to be outstanding, 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 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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