Shareholders' equity (deficit) - Share-based compensation - Weighted average assumptions for the options granted (Details) - Options - $ / 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 | ||||
| Exercise price (in dollars per share) | $ 12.05 | $ 1.54 | $ 11.02 | $ 1.54 |
| Share price (in dollars per share) | $ 12.05 | $ 1.54 | $ 11.02 | $ 1.54 |
| Volatility (as a percent) | 82.00% | 82.00% | 81.00% | 82.00% |
| Risk-free interest rate (as a percent) | 2.36% | 2.73% | 2.41% | 2.77% |
| Expected life (in years) | 6 years 3 months | 6 years 3 months | 6 years 3 months | 6 years 3 months |
| Dividend (as a percent) | 0.00% | 0.00% | 0.00% | 0.00% |
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- Definition Weighted-average fair value exercise price per share during the reporting period for shares granted under share-based payment arrangement. No definition available.
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- Definition Weighted-average fair value price paid per share during the reporting period for shares purchased on open market for issuance under share-based payment arrangement. No definition available.
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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