Other Intangible Assets and Goodwill - Summary of Goodwill Recognized (Details) - EUR (€) € in Millions |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|
| Disclosure of detailed information about intangible assets [line items] | ||
| Goodwill | € 380.6 | € 362.5 |
| Intangible assets with indefinite useful life | 486.5 | 444.5 |
| Total | 867.1 | 807.0 |
| CGU Immunotherapies | ||
| Disclosure of detailed information about intangible assets [line items] | ||
| Goodwill | 369.8 | 352.2 |
| Intangible assets with indefinite useful life | 486.5 | 444.5 |
| Total | 856.3 | 796.7 |
| CGU External Product Sales of JPT | ||
| Disclosure of detailed information about intangible assets [line items] | ||
| Goodwill | 0.5 | 0.5 |
| Intangible assets with indefinite useful life | 0.0 | 0.0 |
| Total | 0.5 | 0.5 |
| CGU External Business of InstaDeep | ||
| Disclosure of detailed information about intangible assets [line items] | ||
| Goodwill | 10.3 | 9.8 |
| Intangible assets with indefinite useful life | 0.0 | 0.0 |
| Total | € 10.3 | € 9.8 |