v3.26.3
Financial Assets and Financial Liabilities - Additional Information (Detail)
€ / shares in Units, € in Thousands
 6 Months Ended 12 Months Ended
Jun. 26, 2026
$ / shares
shares
Apr. 08, 2026
EUR (€)
Jun. 30, 2026
EUR (€)
shares
Jun. 30, 2025
EUR (€)
Dec. 31, 2025
EUR (€)
Dec. 31, 2024
EUR (€)
Jun. 30, 2026
$ / shares
Jun. 30, 2026
EUR (€)
Jun. 25, 2026
€ / shares
Disclosure of financial assets and liabilities [line items]                  
Current borrowings         € 109,902     € 51,105 [1]  
Non recourse factoring amount disposed     € 956   2,679        
Line of credit maximum borrowing capacity         72,550     49,810  
Line of credit cumulative amount drawn         58,758        
Change in fair value of derivative warrant liabilities     7,234            
Common stock par or stated value per share | € / shares                 € 2.4
Allowance account for credit losses of financial assets         1,514     1,220  
Additional allowance account for credit losses of trade and other receivables         4,819     4,714  
Inventories pledged as security for liabilities         11,250     11,704  
Nominal value of property plant and equipment pledged       € 35,000   € 35,000      
Property plant and equipment pledged as security       24,789 24,789 € 24,789   € 24,789  
Percentage of share capital pledged as collateral               100.00%  
Inventories net book value               € 4,534  
Non recourse factoring limit amount     4,000   12,000        
Adjustments For Expected Credit Loss For Trade And Other Receivables [2]     (294) (61)          
Uncollectible balances     649 1,527          
Loan from government entity         3,924     3,852  
Capital increase   € 10,600     66,260     82,519 [1]  
Borrowings               € 208,815  
Percentage of share capital pledged as collateral               100.00%  
Bridge loan   € 5,650              
Trade payables               € 12,100  
Non-current portion of non-current borrowings         54,764     140,146 [1]  
Gains (losses) on change in fair value of derivatives [3]     (7,234) 1,100          
Extended to December 31, 2030 [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings               11,700  
Syndicate Term Loan [Member] | Maturing Through 2030 [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings               55,300  
Bullet Instrument [Member] | Maturing in December 2030 [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings               68,000  
Working Capital Line [Member] | Maturing in December 2030 [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings               34,400  
New Working Capital Line [Member] | Maturing in December 2030 [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings               5,400  
Refinancing Agreement [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Non-current portion of non-current borrowings               12,140  
Factoring of receivables [member]                  
Disclosure of financial assets and liabilities [line items]                  
Current borrowings         € 21,859     € 24,636  
Other Operating Expenses [member]                  
Disclosure of financial assets and liabilities [line items]                  
Adjustments For Expected Credit Loss For Trade And Other Receivables     € 250            
Other Operating Income [member]                  
Disclosure of financial assets and liabilities [line items]                  
Adjustments For Expected Credit Loss For Trade And Other Receivables       € 22          
Top of range [member]                  
Disclosure of financial assets and liabilities [line items]                  
Payments to suppliers term     120 days            
Top of range [member] | Floating interest rate [member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings adjustment to interest rate         5.60%     3.00%  
Top of range [member] | Fixed interest rate [member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings adjustment to interest rate         9.00%     10.00%  
Bottom of range [member]                  
Disclosure of financial assets and liabilities [line items]                  
Payments to suppliers term     90 days            
Bottom of range [member] | Floating interest rate [member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings adjustment to interest rate         0.00%     0.00%  
Bottom of range [member] | Fixed interest rate [member]                  
Disclosure of financial assets and liabilities [line items]                  
Borrowings adjustment to interest rate         3.81%     1.00%  
Class A ordinary shares [member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights exercise price per share | $ / shares $ 2.4           $ 3.05    
Class A ordinary shares [member] | Wallbox and Generac Power Systems, Inc. [Member] | Top of range [member]                  
Disclosure of financial assets and liabilities [line items]                  
Trading days 30 days   30 days            
Class A ordinary shares [member] | Wallbox and Generac Power Systems, Inc. [Member] | Bottom of range [member]                  
Disclosure of financial assets and liabilities [line items]                  
Price Per Share | $ / shares $ 6           6    
Trading days 20 days   20 days            
Warrants Exercisable Until May 8, 2029 [member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights fair value per warrant | $ / shares             0.13    
Warrants Exercisable Until July 30, 2028 [member]                  
Disclosure of financial assets and liabilities [line items]                  
Number of warrants exercisable | shares     229,938            
Warrants Exercisable Until June 26, 2031 [member]                  
Disclosure of financial assets and liabilities [line items]                  
Number of warrants exercisable | shares 3,301,758                
Public warrants [member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights fair value per warrant | $ / shares             0    
Private warrants [member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights fair value per warrant | $ / shares             0    
BBVA warrant [Member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights fair value per warrant | $ / shares             0.31    
Other warrant [member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights fair value per warrant | $ / shares             2.49    
Generac warrant [member] | Warrants Exercisable Until July 30, 2028 [member]                  
Disclosure of financial assets and liabilities [line items]                  
Class of warrants or rights fair value per warrant | $ / shares             $ 0.044    
[1] Unaudited
[2] Unaudited
[3] Unaudited