Other information by nature - Narrative (Details) € in Billions	12 Months Ended
Dec. 31, 2024 EUR (€) employee	Dec. 31, 2023 EUR (€) employee	Dec. 31, 2022 EUR (€) employee
Additional information [abstract]
Personnel costs \| €	€ 17.1	€ 19.1	€ 18.2
Average number of employees \| employee	259,118	271,292	282,926

The expense of all forms of consideration given by an entity in exchange for a service rendered by employees or for the termination of employment.

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