v3.26.1
Other Intangible Assets and Goodwill - Summary of Detailed Information About Intangible Assets (Details) - EUR (€)
€ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance € 790.4  
Impairment   € 85.4
Ending balance 1,606.0 790.4
Gross carrying amount    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 1,044.4 921.0
Additions 573.8 115.2
Disposals (0.1) (2.9)
Reclassifications 0.0 0.0
Currency differences (21.8) 11.1
Additions from business combinations 413.1  
Ending balance 2,009.4 1,044.4
Cumulative depreciation and impairment charges    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance (254.0) (116.9)
Amortization 67.1 54.8
Impairment 88.5 83.3
Disposals 0.0 2.8
Currency differences (6.2) 1.8
Ending balance (403.4) (254.0)
In-process R&D    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 485.5  
Ending balance 473.3 485.5
In-process R&D | Gross carrying amount    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 540.6 443.5
Additions 565.1  
Disposals 0.0 0.0
Reclassifications (644.8) 0.0
Currency differences (14.8) 0.0
Additions from business combinations 167.7  
Ending balance 613.8 540.6
In-process R&D | Cumulative depreciation and impairment charges    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance (55.1) 0.0
Amortization 0.0 0.0
Impairment 85.4 55.1
Disposals 0.0 0.0
Currency differences 0.0 0.0
Ending balance (140.5) (55.1)
Intellectual property rights, licenses, software and similar rights    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 282.2  
Ending balance 1,112.1 282.2
Intellectual property rights, licenses, software and similar rights | Gross carrying amount    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 481.1 455.1
Additions 6.6 6.2
Disposals (0.1) (2.9)
Reclassifications 648.8 11.6
Currency differences (6.8) 11.1
Additions from business combinations 245.4  
Ending balance 1,375.0 481.1
Intellectual property rights, licenses, software and similar rights | Cumulative depreciation and impairment charges    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance (198.9) (116.9)
Amortization 67.1 54.8
Impairment 3.1 28.2
Disposals 0.0 2.8
Currency differences (6.2) 1.8
Ending balance (262.9) (198.9)
Work in progress and advance payments    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 22.7  
Ending balance 20.6 22.7
Work in progress and advance payments | Gross carrying amount    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 22.7 22.4
Additions 2.1 11.9
Disposals 0.0 0.0
Reclassifications (4.0) (11.6)
Currency differences (0.2) 0.0
Additions from business combinations 0.0  
Ending balance 20.6 22.7
Work in progress and advance payments | Cumulative depreciation and impairment charges    
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]    
Beginning balance 0.0 0.0
Amortization 0.0 0.0
Impairment 0.0 0.0
Disposals 0.0 0.0
Currency differences 0.0 0.0
Ending balance € 0.0 € 0.0