Taxation - Summary of Deferred Tax Assets And Liabilities (Detail) - EUR (€) € in Thousands  | 
12 Months Ended | |
|---|---|---|
Dec. 31, 2021  | 
Dec. 31, 2020  | 
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| Deferred tax assets and liabilities [abstract] | ||
| Beginning balance, Deferred tax assets | € 4,573 | € 4,837 | 
| Beginning balance, Deferred tax liabilities | (3,851) | (4,837) | 
| Beginning balance, Net deferred tax assets | 722 | 0 | 
| Recognition of losses | (859) | 859 | 
| Movements of temporary differences | 974 | (386) | 
| Recognition of tax credits | (267) | 249 | 
| Ending Balance,Deferred tax assets | 8,209 | 4,573 | 
| Ending Balance, Deferred tax liabilities | (7,639) | (3,851) | 
| Ending Balance,Net deferred tax assets | € 570 | € 722 | 
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- Definition Deferred tax liability. No definition available. 
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- Definition Income tax relating to components Movements of temporary differences. No definition available. 
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- Definition Income tax relating to components Recognition of tax credits. No definition available. 
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- Definition The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- References No definition available. 
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- Definition The amount of tax expense or income relating to changes in deferred tax liabilities and deferred tax assets, recognised in profit or loss. [Refer: Deferred tax assets; Deferred tax expense (income); Deferred tax liabilities] Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The amount of deferred tax assets net of deferred tax liabilities, when the absolute amount of deferred tax assets is greater than the absolute amount of deferred tax liabilities. [Refer: Deferred tax assets; Deferred tax liabilities] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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