v3.25.4
Intangible assets - Summary of Amortization expense (Detail) - EUR (€)
€ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of detailed information about intangible assets [line items]      
Amortisation, intangible assets other than goodwill € (138) € (182) € (223)
Research and development expenses [Member]      
Disclosure of detailed information about intangible assets [line items]      
Amortisation, intangible assets other than goodwill (79) (98) (115)
General and administrative expenses [Member]      
Disclosure of detailed information about intangible assets [line items]      
Amortisation, intangible assets other than goodwill € (59) € (84) € (108)