v3.26.1
Operating expenses - Disclosure of Other Operating Income (Expense) (Details)
€ in Thousands, $ in Millions
12 Months Ended
Dec. 31, 2025
EUR (€)
Dec. 31, 2024
EUR (€)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
EUR (€)
Analysis of income and expense [abstract]        
Other operating expenses € (21) € (136)   € (2,542)
Other operating income 85 3   0
Total Other operating income and expenses 64 (134)   (2,542)
Disclosure Of Operating Expenses [Line Items]        
Termination benefits expense 64 129   700
Revenues € 29,643 (11,609)   30,058
Janssen        
Disclosure Of Operating Expenses [Line Items]        
Revenues   € (1,600)   € (1,600)
Termination of PharmaEngine License and Collaboration Agreement, NBTXR3        
Disclosure Of Operating Expenses [Line Items]        
Contract termination indemnities | $     $ 1.0