Share-based compensation - Options (Details) - $ / shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
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| Share-based compensation | ||||
| Number of options granted (in shares) | 936,696 | 1,435,685 | 11,743,896 | 11,430,341 |
| Weighted average fair value (in dollars per share) | $ 0.39 | $ 1.18 | $ 0.54 | $ 0.80 |
| Number of additional options with a nominal exercise price granted | 459,240 | 151,056 | 6,957,366 | 6,703,692 |
| Weighted average fair value of options with a nominal exercise price | $ 0.70 | $ 1.88 | $ 0.93 | $ 1.35 |
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the nominal exercise price. No definition available.
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- Definition Gross number of share options (or share units) granted with nominal exercise price during the period. No definition available.
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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://fasb.org/us-gaap/role/ref/legacyRef
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