Share-based payments - Service conditions (Details) - ESOP 2014 $ / shares in Units, € in Millions, $ in Millions	12 Months Ended
Dec. 31, 2023 EUR (€) EquityInstruments shares	Dec. 31, 2023 USD ($) EquityInstruments shares $ / shares	Dec. 31, 2022 EquityInstruments shares $ / shares
Share-based payments with service condition
Vesting period (in years)	3 years	3 years
Exercise period	10 years	10 years
Awards granted (share option) \| EquityInstruments	822,175	822,175	491,560
Fair value of the awards at grant date (Share option).	€ 6.0	$ 6.4
Awards cancelled or forfeited (Share option) \| EquityInstruments	167,260	167,260	27,743
Awards exercised (Share options) \| shares	0	0	4,344
Weighted average exercise price of share options exercised. \| $ / shares			$ 25.2
Awards outstanding (options) \| EquityInstruments		2,181,888	1,526,973
Awards Vested (Share options) \| EquityInstruments	1,240,852	1,240,852	851,086
Weighted average remaining contractual life	7 years 3 months 18 days	7 years 3 months 18 days	7 years 4 months 24 days
Weighted average exercise price \| $ / shares		$ 35.7	$ 49.1
Annual forfeiture rate	4.00%	4.00%	4.00%
Minimum
Share-based payments with service condition
Exercise price \| $ / shares		$ 3.5	$ 13.0
Maximum
Share-based payments with service condition
Exercise price \| $ / shares		$ 134.7	$ 134.7

The period over which shares can be exercised from grant date.

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The percentage of share options forfeited.

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The fair value of share options at the grant date.

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No definition available.

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Period which the right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of options vested in a share-based payment arrangement.

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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 outstanding share options.

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- Definition

The number of share options outstanding in a share-based payment arrangement.

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The number of share options exercised in a share-based payment arrangement.

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The number of share options forfeited in a share-based payment arrangement.

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The number of share options granted in a share-based payment arrangement.

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The weighted average exercise price of share options exercised in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average remaining contractual life of outstanding share options. [Refer: Weighted average [member]]

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