Audit fees - Summary of audit and non-audit services (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fees of Group's auditor
Audit fees	€ 29	€ 27	€ 27
Audit related fees	1
Total	€ 30	€ 27	€ 27

The amount of fees paid or payable to the entity's auditors.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 112
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-URIDate 2023-03-23

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- References

No definition available.

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- Definition

The amount of fees paid or payable to the entity's auditors for auditing services.

+ References

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- Definition

The amount of fees paid or payable to the entity's auditors for services that the entity does not separately disclose in the same statement or note.

+ References

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