Share-based compensation - Options (Details) - $ / shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2016 |
Jun. 30, 2015 |
Jun. 30, 2016 |
Jun. 30, 2015 |
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| Share-based compensation | ||||
| Number of options granted (in shares) | 1,768,243 | 1,885,615 | 15,343,797 | 11,069,517 |
| Weighted average fair value (in dollars per share) | $ 0.89 | $ 1.45 | $ 0.70 | $ 0.94 |
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- References 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 The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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