Derivative financial instruments and hedge accounting - Underlying asset or liability by type of risk hedged under fair value hedge (Details) - Fair value hedge derivatives € in Millions	12 Months Ended
Dec. 31, 2024 EUR (€)
Currency risk \| Hedge fund investments [member]
Derivative financial instruments and hedge accounting
Nominal amount of the underlying item	43
Cumulative changes of the underlying item, assets	€ (2)
Change of the underlying item	€ (2)
Interest rate risk \| Financial liabilities [Member]
Derivative financial instruments and hedge accounting
Nominal amount of the underlying item	2,066
Cumulative changes of the underlying item, liabilities	€ 44
Change of the underlying item	€ 44

Disclosure of derivative financial instruments

No definition available.

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- Definition

The nominal amount of the underlying hedged item.

+ References

No definition available.

+ Details

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- Definition

The accumulated amount of fair value hedge adjustment on a hedged item that is included in the carrying amount of the hedged item, recognised in the statement of financial position as an asset. [Refer: Hedged items [domain]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24B
-Subparagraph a
-Clause ii
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24B_a_ii&doctype=Standard
-URIDate 2024-03-27

+ Details

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- Definition

+ References

+ Details

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- Definition

The gain (loss) on the change in fair value of the hedged item used as a basis for recognising hedge ineffectiveness. Hedge ineffectiveness is the extent to which the changes in the fair value or the cash flows of the hedging instrument are greater or less than those on the hedged item.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24B
-Subparagraph a
-Clause iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24B_a_iv&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 24B
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_24B_b_i&doctype=Standard
-URIDate 2024-03-27

+ Details

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- Details

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- Details

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