v3.26.1
Property, plant and equipment - Fully Owned (Details) - EUR (€)
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance € 105,399,000  
Ending balance 71,946,000 € 105,399,000
Assets Related To Small Molecule [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Impairment (9,600,000)  
Acquisition value    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 143,291,000 146,507,000
Additions 12,428,000 17,303,000
Sales and disposals (31,537,000) (9,677,000)
Reclassifications to assets in disposal group classified as held for sale   (11,115,000)
Translation differences (1,274,000) 273,000
Ending balance 122,908,000 143,291,000
Depreciations and impairment    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance (37,892,000) (35,287,000)
Depreciation (10,351,000) (11,076,000)
Impairment (32,716,000) (1,243,000)
Sales and disposals 29,448,000 9,677,000
Translation differences 549,000 37,000
Ending balance (50,962,000) (37,892,000)
Land, buildings and leasehold improvements    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 75,066,000  
Impairment (3,600,000)  
Ending balance 66,826,000 75,066,000
Land, buildings and leasehold improvements | Acquisition value    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 86,014,000 90,705,000
Additions 1,622,000 7,292,000
Sales and disposals (758,000) (6,554,000)
Reclassifications (1,283,000) 4,687,000
Reclassifications to assets in disposal group classified as held for sale   (10,200,000)
Translation differences (606,000) 84,000
Ending balance 84,989,000 86,014,000
Land, buildings and leasehold improvements | Depreciations and impairment    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance (10,948,000) (11,218,000)
Depreciation (4,021,000) (5,284,000)
Impairment (4,155,000) (1,068,000)
Sales and disposals 758,000 6,554,000
Translation differences 203,000 68,000
Ending balance (18,163,000) (10,948,000)
Installation and machinery    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 25,926,000  
Ending balance 2,664,000 25,926,000
Installation and machinery | Acquisition value    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 49,284,000 39,678,000
Additions 10,788,000 9,595,000
Sales and disposals (29,284,000) (663,000)
Reclassifications 1,813,000 470,000
Translation differences (667,000) 204,000
Ending balance 31,934,000 49,284,000
Installation and machinery | Depreciations and impairment    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance (23,358,000) (19,178,000)
Depreciation (5,562,000) (4,787,000)
Impairment (27,900,000) (17,000)
Sales and disposals 27,205,000 663,000
Translation differences 345,000 (39,000)
Ending balance (29,270,000) (23,358,000)
Furniture, fixtures & vehicles    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 3,876,000  
Ending balance 2,455,000 3,876,000
Furniture, fixtures & vehicles | Acquisition value    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 7,462,000 9,353,000
Additions 18,000 118,000
Sales and disposals (1,495,000) (2,460,000)
Reclassifications   466,000
Translation differences (1,000) (15,000)
Ending balance 5,984,000 7,462,000
Furniture, fixtures & vehicles | Depreciations and impairment    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance (3,586,000) (4,891,000)
Depreciation (768,000) (1,005,000)
Impairment (661,000) (158,000)
Sales and disposals 1,485,000 2,460,000
Translation differences 1,000 8,000
Ending balance (3,529,000) (3,586,000)
Other tangible assets    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 530,000  
Impairment (100,000)  
Ending balance   530,000
Other tangible assets | Acquisition value    
Disclosure of detailed information about property, plant and equipment [line items]    
Beginning balance 530,000 6,770,000
Additions   298,000
Reclassifications (530,000) (5,623,000)
Reclassifications to assets in disposal group classified as held for sale   (915,000)
Ending balance   € 530,000
Lab Equipment [member]    
Disclosure of detailed information about property, plant and equipment [line items]    
Impairment € (19,400,000)