Investment and return - Narrative (Details) - EUR (€) € in Millions	Dec. 31, 2025	Dec. 31, 2024
Investment And Return [Abstract]
Cash and cash equivalents held by central finance companies	€ 600
Percentage of cash and cash equivalents held by central finance companies	15.00%
Cash and cash equivalents held with foreign subsidiaries	€ 3,300
Percentage of cash and cash equivalents held with foreign subsidiaries	85.00%
Cash and cash equivalents held by entity unavailable for use by group	€ 160	€ 176
Collateral held permitted to be sold or repledged in absence of default by owner of collateral, at fair value	€ 28	€ 89

The fair value of collateral held that is permitted to be sold or repledged in the absence of default by the owner of the collateral. [Refer: At fair value [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2025-01-01
-Paragraph 15
-Subparagraph a
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The amount of significant cash and cash equivalent balances held by the entity that are not available for use by the group. [Refer: Cash and cash equivalents]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
-IssueDate 2025-01-01
-Paragraph 48
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2025-en-r&anchor=para_48&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 171
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_171&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
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Cash and cash equivalents held by central finance companies.

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Cash and cash equivalents held by central finance companies percentage.

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Cash and cash equivalents held by foreign subsidiaries.

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Cash and cash equivalents held by foreign subsidiaries percentage.

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Investment And Return

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