Commitments and contingent liabilities - Narrative (Details) - EUR (€) € in Millions	Dec. 31, 2025	Dec. 31, 2024
Brazil
Disclosure of contingent liabilities [line items]
Corporate reorganisation tax assessment	€ 3,557	€ 3,230

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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