Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Significant accounting estimates, assumptions and judgments - Additional Information (Detail)

v3.22.1
Significant accounting estimates, assumptions and judgments - Additional Information (Detail) - EUR (€)
€ in Thousands
 1 Months Ended 12 Months Ended 20 Months Ended
Jul. 28, 2021
Dec. 31, 2019
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2019
Apr. 22, 2021
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Share capital     € 1 € 1      
Percentage of voting equity interests acquired     100.00%        
Deferred tax assets   € 4,837 € 8,209 4,573 € 4,837 € 4,837  
Impairments of property, plant and equipment     354 466 272    
Reversal of impairments loss     € 381 0 0    
Chargers [Member]              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Percentage of up time an equipment being functional without technical issues     95.00%        
Impairments of property, plant and equipment     € 354 466 272    
Reversal of impairments loss     381 0 0    
DE And BE [Member]              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Deferred tax assets     570        
GERMANY              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Deferred tax assets       722      
Consultancy Firm [Member] | Madeline [Member] | Amendment To Special Fees Agreement [Member]              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Amended agreement provides right to subscribe additional shares percentage of share capital as A consideration for services after completion of listing             5.00%
Mega E [Member]              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Consideration paid (received) € 0 0          
Share capital   € 100     € 100 € 100  
Percentage of voting equity interests acquired 100.00%            
Percentage of shares and voting rights held           100.00%  
Mega E [Member] | Call Option Agreement [Member]              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Percentage of voting equity interests acquired 100.00%            
Computer software [member]              
Disclosure Of Significant Accounting Estimates Assumptions And Judgements [Line Items]              
Carrying value of capitalized development costs     € 4,198 € 3,812      
Useful life measured as period of time, intangible assets other than goodwill     3 years        
Description of useful life intangible assets other than goodwill     actual useful life may be shorter or longer than three years, depending on innovations, market developments and competitor actions.