Other disclosures - Credit and debt valuation adjustments (CVA, DVA) (Details) € in Millions	6 Months Ended
Jun. 30, 2020 EUR (€)
Disclosure of detailed information about financial instruments [line items]
Amount of CVA	€ 477.4
Change in CVA (as a percent)	75.50%
Amount of DVA	€ 250.1
Change in DVA (as a percent)	46.20%
Minimum
Disclosure of detailed information about financial instruments [line items]
Credit spread change (as a percent)	30.00%

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]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 9
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_9_c&doctype=Standard
-URIDate 2019-03-27

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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 2019-01-01
-Paragraph 10
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_10_a&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2019-01-01
-Paragraph 10A
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2019-en-r&anchor=para_10A_a&doctype=Standard
-URIDate 2019-03-27

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

Increase (decrease) in credit valuation adjustment from prior year as a percent.

+ References

No definition available.

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- Definition

Increase (decrease) in debt valuation adjustment from prior year as a percent.

+ References

No definition available.

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- Definition

The percentage change in credit spreads likely to trigger changes in valuation adjustment.

+ References

No definition available.

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