Investment - Summary of detailed information about investment Property (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Rental income from investment property, net of direct operating expense [abstract]
Rental income reported as part of investment income	€ 68	€ 87	€ 83
Direct operating expenses (Including repairs and maintenance expenses):
- From investment property that generated rental income	32	47	59
- From investment property that did not generate rental income	€ 2	€ 2	€ 2

No definition available.

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- Definition

The amount of direct operating expenses (including repairs and maintenance) arising from investment property that generated rental income during the period recognised in profit or loss. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2021-01-01
-Paragraph 75
-Subparagraph f
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2021-en-r&anchor=para_75_f_ii&doctype=Standard
-URIDate 2021-03-24

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- Definition

The amount of direct operating expenses (including repairs and maintenance) arising from investment property that did not generate rental income during the period recognised in profit or loss. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2021-01-01
-Paragraph 75
-Subparagraph f
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2021-en-r&anchor=para_75_f_iii&doctype=Standard
-URIDate 2021-03-24

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- Definition

The amount of rental income arising from investment property recognised in profit or loss. [Refer: Investment property]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 40
-IssueDate 2021-01-01
-Paragraph 75
-Subparagraph f
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=40&code=ifrs-tx-2021-en-r&anchor=para_75_f_i&doctype=Standard
-URIDate 2021-03-24

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- References

No definition available.

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