v3.26.1
Insurance contracts linked to pensions (Details) - EUR (€)
€ in Millions
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of reconciliation of changes in insurance contracts by remaining coverage and incurred claims [line items]      
Insurance contracts that are assets € 67 € 81 € 93
Banco Santander, S.A.      
Disclosure of reconciliation of changes in insurance contracts by remaining coverage and incurred claims [line items]      
Insurance contracts that are assets € 67 € 81 € 93