v3.25.4

Tax on Profit/(Loss) for the Year and Deferred Tax - Additional Information (Detail) - EUR (€) € in Thousands | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Disclosure of temporary difference, unused tax losses and unused tax credits [line items] |  |  |
Deferred tax assets, not recognized | € 721,631 | € 599,476 | € 537,953
Tax losses carryforwards other temporary deductible differences amount | 3,280,000 |  |
Tax losses carryforwards | 1,954,600 | 1,946,200 | 2,371,300
Income taxes refund | 700 | 700 | 700
Additional future tax deduction related to share based payments | € 67,000 | 21,700 | 10,600
Future tax period | 20 years |  |
Additional tax deductions related to tax credits | € 29,700 | € 24,800 | € 8,400
Revenue threshold limit | € 750,000 |  |

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