Share-based compensation - Options (Details) - $ / shares |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2021 |
Sep. 30, 2020 |
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| Share-based compensation | ||||
| Number of options granted (in shares) | 4,170,230 | 1,882,966 | 19,891,334 | 14,851,182 |
| Weighted average fair value (in dollars per share) | $ 0.51 | $ 1.25 | $ 0.70 | $ 0.57 |
| Number of additional options with a nominal exercise price granted | 1,348,920 | 571,320 | 16,008,168 | 7,410,136 |
| Weighted average fair value of RSU-style options granted | $ 0.70 | $ 1.70 | $ 0.98 | $ 0.78 |
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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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