Provisions and other liabilities - Summary of Restructuring Provision (Detail) - EUR (€) € in Thousands  | 
12 Months Ended | |
|---|---|---|
Dec. 31, 2023  | 
Dec. 31, 2022  | 
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| Disclosure Of Additional Provisions Other Provisions [Line Items] | ||
| Beginning Balance | € 17,743 | |
| Ending balance | 30,436 | € 17,743 | 
| Restructuring provision | ||
| Disclosure Of Additional Provisions Other Provisions [Line Items] | ||
| Current portion Beginning Balance | 144 | 248 | 
| Non-current portion Beginning Balance | 0 | 0 | 
| Beginning Balance | 144 | 248 | 
| Additions | 60 | 0 | 
| Releases | 0 | |
| Used during the year | (142) | (104) | 
| Interest accretion | 0 | 0 | 
| Current portion Ending Balance | 62 | 144 | 
| Non-current portion Ending Balance | 0 | 0 | 
| Ending balance | € 62 | € 144 | 
| X | ||||||||||
- Definition Disclosure Of Additional Provisions Other Provisions. No definition available. 
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- Definition Interest accretion Other Provision No definition available. 
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- Definition The amount of additional other provisions made. [Refer: Other provisions] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The decrease in other provisions resulting from the transfer of those provisions to liabilities included in disposal groups classified as held for sale. [Refer: Other provisions; Disposal groups classified as held for sale [member]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition The amount of non-current provisions other than provisions for employee benefits. [Refer: Non-current provisions] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The amount of provisions other than provisions for employee benefits. [Refer: Provisions] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The amount of current provisions other than provisions for employee benefits. [Refer: Provisions] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The amount used (ie incurred and charged against the provision) for other provisions. [Refer: Other provisions] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Details 
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