Share-based payments - Fair value of options (Details)	12 Months Ended
Dec. 31, 2023 USD ($) EUR (€) $ / shares	Dec. 31, 2022 USD ($) EUR (€) $ / shares
Share-based payments with service condition
Share-based payments
Fair value at grant date \| $	$ 7.8	$ 31.9
Share price at grant date \| $ / shares	$ 10.4	$ 42.9
Exercise price \| $ / shares	$ 10.4	$ 42.9
Expected volatility	90.00%	90.00%
Expected life \| €	5.9	5.9
Expected dividends \| $	$ 0.0	$ 0.0
Risk-free interest rate	3.95%	2.32%
Share-based payments with market condition
Share-based payments
Fair value at grant date \| $		$ 11.3
Share price at grant date \| $ / shares		$ 45.8
Exercise price \| $ / shares		$ 45.8
Expected volatility		70.00%
Expected life \| €		2.00
Expected dividends \| $		$ 0.00
Risk-free interest rate		2.41%

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

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The option life of share options granted.

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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The exercise price of share options granted.

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The amount of an expected dividend used to calculate the fair value of share options granted.

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The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

+ References

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The weighted average share price. [Refer: Weighted average [member]]

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