v3.26.1
Dividends paid and proposed - Schedule of Gross Dividends Declared and Paid (Parenthetical) (Detail) - € / shares
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Class A Shares [Member]      
Disclosure Of Gross Dividends Declared And Paid [Line Items]      
Dividends paid, other shares per share € 0.25 € 0.5 € 0.5
Interim Dividend Paid Per Share 0.25 0.25  
Class B Shares [Member]      
Disclosure Of Gross Dividends Declared And Paid [Line Items]      
Dividends paid, other shares per share 0.1 0.2 € 0.2
Interim Dividend Paid Per Share € 0.1 € 0.1