Risk management - Structural equity risk (Details) - Equities - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure of nature and extent of risks arising from financial instruments [line items]
VaR	€ 5.1	€ 3.1	€ 4.8
Equity instruments
Disclosure of nature and extent of risks arising from financial instruments [line items]
VaR percentage	99.00%
Time horizon	1 day
VaR	€ 325.0	€ 319.0	€ 170.0

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

No definition available.

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- Definition

The measure of a potential loss exposure as a result of future market movements, based on a specified confidence interval and measurement horizon.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 41
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-URIDate 2021-03-24

+ Details

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- Definition

The specified confidence level percentage used to measure potential loss exposure due to the effects of future market movements on value at risk.

+ References

No definition available.

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- Definition

The measurement horizon for the calculation of value at risk, i.e., losses per this number of days.

+ References

No definition available.

+ Details

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