v3.26.3
Intangible assets - Additional information (Details) - EUR (€)
€ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Jun. 30, 2025
Disclosure of detailed information about intangible assets [line items]      
Intangible assets other than goodwill € 0  
2014 Monalizumab (NKG2A) agreement with Novo Nordisk      
Disclosure of detailed information about intangible assets [line items]      
Intangible assets other than goodwill € 0   € 0