Stock-based compensation - Stock option grants (Details) - Employee Stock Option [Member] - $ / shares |
1 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Nov. 30, 2014 |
Aug. 31, 2014 |
Jun. 30, 2014 |
Feb. 28, 2014 |
Dec. 31, 2015 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Number of shares | 115,000 | 275,000 | 690,000 | 200,000 | 0 |
| Exercise price (in dollars per share) | $ 4.90 | $ 5.00 | $ 4.85 | $ 6.00 | $ 0.00 |
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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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