Share-based compensation - Options (Details) - $ / shares |
3 Months Ended | |
|---|---|---|
Mar. 31, 2017 |
Mar. 31, 2016 |
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| Share-based compensation | ||
| Number of options granted (in shares) | 18,950,976 | 13,575,554 |
| Weighted average fair value (in dollars per share) | $ 0.34 | $ 0.89 |
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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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