v3.25.4
Income taxes - Text Details (Detail) - EUR (€)
€ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Income taxes [Abstract]      
Income tax (expense) benefit € 282.0 € 963.0 € (73.0)
Tax expense (income) relating to profit (loss) from ordinary activities of discontinued operations 4.0 143.0 € 9.0
Current tax expense (income), related to Pillar Two income taxes € 1.3 € 1.0  
Effective tax rate increase (decrease) related to Pillar Two income tax 0.10% 0.40%  
Decrease in current tax expense related to Pillar Two income taxes € 0.6    
Impact on the current year ETR of the Pillar 2 prior year true-up 0.0005    
Net deferred tax assets € 1,681.0 € 1,835.0  
Deferred tax assets 1,773.0 1,916.0  
Deferred tax liabilities 93.0 81.0  
Deferred tax asset when utilisation is dependent on future taxable profits in excess of profits from reversal of taxable temporary differences and entity has suffered loss in jurisdiction to which deferred tax asset relates 1,070.0 1,188.0  
Deductible temporary differences for which no deferred tax asset is recognised 352.0 788.0  
Temporary differences associated with investments in subsidiaries, branches and associates and interests in joint arrangements for which deferred tax liabilities have not been recognised 284.0 340.0  
Other tax liability € 70.0 € 116.0