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Fair value of financial instruments - Narrative (Details) € in Millions | 12 Months Ended
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Dec. 31, 2025 EUR (€) independent_division | Dec. 31, 2024 EUR (€) | Dec. 31, 2023 EUR (€)
Fair Value of Financial Instruments [Abstract] |  |  |
Number of independent divisions | independent_division | 2 |  |
Amount of CVA | € 224 | € 272 | € 293
Change in CVA (as a percent) | 17.60% | 7.20% | 16.50%
Amount of DVA | € 285 | € 317 | € 330
Change in DVA (as a percent) | 10.10% | 3.90% | 9.30%
Gain (loss) recognized in profit and loss | € 469 | € 523 | € 404

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- Definition The accumulated increase (decrease) in the fair value of financial assets designated as measured at fair value through profit or loss that is attributable to changes in the credit risk of the assets determined either: (a) as the amount of change in their fair value that is not attributable to changes in market conditions that gave rise to market risk; or (b) using an alternative method that the entity believes more faithfully represents the amount of change in its fair value that is attributable to changes in the credit risk of the asset. [Refer: Credit risk [member]; Market risk [member]; Increase (decrease) in fair value of financial assets designated as measured at fair value through profit or loss, attributable to changes in credit risk of financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2025-01-01 -Paragraph 9 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_9_c&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition The accumulated increase (decrease) in the fair value of financial liabilities that is attributable to changes in the credit risk of the liabilities. [Refer: Credit risk [member]; Market risk [member]; Increase (decrease) in fair value of financial liability, attributable to changes in credit risk of liability] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2025-01-01 -Paragraph 10 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_10_a&doctype=Standard -URIDate 2025-03-27 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2025-01-01 -Paragraph 10A -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2025-en-r&anchor=para_10A_a&doctype=Standard -URIDate 2025-03-27 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 45 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_45_a&doctype=Standard -URIDate 2025-03-27 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 46 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_46_a&doctype=Standard -URIDate 2025-03-27 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 45 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_45_a&doctype=Standard -URIDate 2025-03-27 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Note Effective 2027-01-01 -Name IFRS -Number 19 -IssueDate 2025-01-01 -Paragraph 46 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_46_a&doctype=Standard -URIDate 2025-03-27 + Details
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- Definition Fair value of financial instruments [Abstract] + References No definition available. + Details
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- Definition Increase (decrease) in credit valuation adjustment from prior year as a percent. + References No definition available. + Details
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- Definition Increase (decrease) in debt valuation adjustment from prior year as a percent. + References No definition available. + Details
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- Definition Number of independent divisions from which responsibilities are distributed for the systematic valuation and management of financial instruments. + References No definition available. + Details
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- Definition The net gains (losses) recognised in profit or loss on the fair value measurement of assets and liabilities. + References No definition available. + Details
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