v3.25.4
Share-based payments - Summary of Employee Related Share Based Compensation Expense (Detail) - EUR (€)
€ in Thousands
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure Of Detailed Information About Share Based Compensation Expense [Line Items]      
Share-based compensation expense € (15,015) € (17,642) € (20,705)
Research and development expenses [Member]      
Disclosure Of Detailed Information About Share Based Compensation Expense [Line Items]      
Share-based compensation expense (7,538) (9,587) (11,972)
General and administrative expenses [Member]      
Disclosure Of Detailed Information About Share Based Compensation Expense [Line Items]      
Share-based compensation expense € (7,477) € (8,055) € (8,733)