v3.26.1
Investments - Additional Information (Detail) - EUR (€)
€ in Millions
Dec. 31, 2025
Dec. 31, 2024
Disclosure of investments in financial assets and real estate [line items]    
Financial assets € 69,293 € 76,020
Debt Securities Money Market And Other Shortterm Instruments [Member]    
Disclosure of investments in financial assets and real estate [line items]    
Financial assets € 5,774 € 6,106