v3.26.1
Derivative financial instruments and hedge accounting - Underlying asset or liability by type of risk hedged under fair value hedge (Details) - Fair value hedge derivatives
€ in Millions
12 Months Ended
Dec. 31, 2025
EUR (€)
Dec. 31, 2024
EUR (€)
Currency risk | Hedge fund investments [member]    
Derivative financial instruments and hedge accounting    
Nominal amount of the underlying item   43
Cumulative changes of the underlying item, assets   € (2)
Change of the underlying item   € (2)
Interest rate risk | Financial liabilities [Member]    
Derivative financial instruments and hedge accounting    
Nominal amount of the underlying item 2,008 2,066
Cumulative changes of the underlying item, liabilities € 39 € 44
Change of the underlying item € (5) € 44