Other Equity Instruments - Summary of Coupon Details - Summary of Perpetual Contingent Convertible (Parenthetical) (Detail) € in Millions	Dec. 31, 2021 EUR (€)
EUR 500 million [member] \| Perpetual contingent convertible securities [member]
Disclosure of other equity instruments [line items]
Principal amount	€ 500

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 112
-Subparagraph c
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-URIDate 2021-03-24

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