Reserves - Additional Information (Detail) - EUR (€) € in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2021  | 
Dec. 31, 2020  | 
Dec. 31, 2019  | 
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| Text Block [Abstract] | |||
| Net changes In legal reserve | € 386 | € 777 | € 2,028 | 
| X | ||||||||||
- Definition Net Changes In Legal Reserve. No definition available. 
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- Definition Text block. No definition available. 
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