v3.25.4
Related party disclosures - Summary of Compensation for the Supervisory Board (Detail) - EUR (€)
€ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation € 475 € 429 € 348
Share-based compensation expense 1,977 2,192 1,318
Total cash compensation 2,452 2,621 1,666
Peter Chambre [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 90 85 80
Share-based compensation expense 239 285 203
Total cash compensation 329 370 283
Michael G. Atieh [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 70 68 60
Share-based compensation expense 239 285 203
Total cash compensation 309 353 263
Paul Carter [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 65 63 56
Share-based compensation expense 239 285 203
Total cash compensation 304 348 259
Heather L. Mason [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 50 48 43
Share-based compensation expense 239 285 203
Total cash compensation 289 333 246
Adam Stone [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 50 48 43
Share-based compensation expense 239 285 203
Total cash compensation 289 333 246
Nancy Valente [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation     23
Share-based compensation expense     97
Total cash compensation     120
Mathias Hothum [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 50 48  
Share-based compensation expense 236 269  
Total cash compensation 286 317  
Eliot Forster [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 50 48 43
Share-based compensation expense 239 287 206
Total cash compensation 289 335 € 249
Alise Reicin [Member]      
Disclosure of amounts incurred by entity for provision of key management personnel services provided by separate management entities [line items]      
Supervisory board compensation 50 21  
Share-based compensation expense 307 211  
Total cash compensation € 357 € 232