v3.26.3
Intangible Assets and Goodwill - Additional Information (Detail) - EUR (€)
 6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Disclosure of detailed information about intangible assets [line items]    
Additions other than through business combinations, intangible assets other than goodwill € 3,444,000  
Fully amortised intangible assets 28,838,000 € 7,058,000
Intangible assets other than goodwill 40,595,000 [1] 39,778,000
Additions of intangible assets pending of payment 706,000 555,000
Commitments for acquisition of intangible assets 193,000 551,000
Impairment losses on non current assets € 0 26,755,000
Bottom of Range    
Disclosure of detailed information about intangible assets [line items]    
Average remaining amortization term 3 years  
Top of Range    
Disclosure of detailed information about intangible assets [line items]    
Average remaining amortization term 5 years  
Trademarks    
Disclosure of detailed information about intangible assets [line items]    
Intangible assets other than goodwill € 91,000 381,000
Impairment losses on non current assets   14,259,000
Customer Relationships    
Disclosure of detailed information about intangible assets [line items]    
Intangible assets other than goodwill 1,624,000 1,777,000
Computer software    
Disclosure of detailed information about intangible assets [line items]    
Additions other than through business combinations, intangible assets other than goodwill 70,000 334,000
Intangible assets other than goodwill 6,009,000 6,227,000
Impairment losses on non current assets   2,761,000
Capitalised development expenditure [member]    
Disclosure of detailed information about intangible assets [line items]    
Additions other than through business combinations, intangible assets other than goodwill 3,374,000 8,435,000
Intangible assets other than goodwill 32,871,000 31,393,000
Impairment losses on non current assets   6,670,000
Internally generated [member] | Capitalised development expenditure [member]    
Disclosure of detailed information about intangible assets [line items]    
Intangible assets other than goodwill € 3,069,000 € 7,402,000
[1] Unaudited