Stock-based compensation - Stock option grants (Details) - $ / shares |
12 Months Ended | |||||
|---|---|---|---|---|---|---|
Sep. 19, 2016 |
Sep. 06, 2016 |
Apr. 08, 2016 |
Apr. 01, 2016 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Employee Stock Option | ||||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||
| Number of shares | 30,000 | 30,000 | 1,000,000 | 250,000 | 560,000 | 0 |
| Exercise price (in dollars per share) | $ 2.39 | $ 2.61 | $ 2.73 | $ 2.83 | $ 2.72 | |
| Options Granted Upon Achievement of Certain Milestones | ||||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||
| Number of shares | 625,000 | 125,000 | ||||
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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- Details
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- Details
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