Commitments and contingencies - Additional Information (Detail) - EUR (€) € in Thousands  | 
6 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2022  | 
Dec. 31, 2021  | 
Dec. 31, 2020  | 
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| Statement of Commitments and Contingencies [Abstract] | |||
| Purchase commitments for chargers and charging infrastructure | € 2,627 | € 2,261 | € 4,354 | 
| X | ||||||||||
- Definition Purchase commitments for chargers and charging infrastructure. No definition available. 
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| X | ||||||||||
- Definition Statement of commitments and contingencies. No definition available. 
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