Summary of personnel expenses (Details) € in Millions	12 Months Ended
Dec. 31, 2023 EUR (€) employee	Dec. 31, 2022 EUR (€) employee	Dec. 31, 2021 EUR (€) employee
Classes of employee benefits expense [abstract]
Salaries and wages	€ 5,988	€ 6,439	€ 6,191
Defined contribution plans	251	241	223
Defined benefit plan	156	193	183
Share-based payments	202	149	118
Social security costs	873	881	826
Total	€ 7,470	€ 7,903	€ 7,541
Average number of employees \| employee	86,689	86,896	87,927

The average number of personnel employed by the entity during a period.

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No definition available.

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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.

+ References

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The amount of expense from share-based payment transactions with employees. [Refer: Expense from share-based payment transactions]

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The amount of post-employment benefit expense included in profit or loss relating to defined benefit plans. [Refer: Profit (loss); Defined benefit plans [member]] [Contrast: Increase (decrease) in net defined benefit liability (asset) resulting from expense (income) in profit or loss]

+ References

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The amount of post-employment benefit expense relating to defined contribution plans. Defined contribution plans are post-employment benefit plans under which an entity pays fixed contributions into a separate entity (a fund) and will have no legal or constructive obligation to pay further contributions if the fund does not hold sufficient assets to pay all employee benefits relating to employee service in the current and prior periods.

+ References

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A class of employee benefits expense that represents social security contributions. [Refer: Employee benefits expense]

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A class of employee benefits expense that represents wages and salaries. [Refer: Employee benefits expense]

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