Investments - Summary of Investments in Real Estate (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disclosure of detailed information about investment property [abstract]
Beginning balance	€ 2,385	€ 2,901
Additions	47	148
Subsequent expenditure capitalized	1	2
Disposals	(60)	(726)
Transfer from real estate for own use and equipment	14
Fair value gains / (losses)	253	74
Net exchange differences	3	(14)
Ending balance	€ 2,643	€ 2,385

The amount of additions to investment property resulting from acquisitions. [Refer: Investment property]

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The amount of additions to investment property resulting from subsequent expenditure recognised as an asset. [Refer: Investment property]

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No definition available.

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The decrease in investment property resulting from disposals. [Refer: Investment property]

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The gains (losses) from changes in the fair value of investment property. [Refer: Investment property]

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The increase (decrease) in investment property resulting from net exchange differences arising on the translation of the financial statements from the functional currency into a different presentation currency, including the translation of a foreign operation into the presentation currency of the reporting entity. [Refer: Investment property]

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The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee as a right-of-use asset) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business.

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The amount transferred from (to) inventories and owner-occupied property to (from) investment property. [Refer: Inventories; Investment property]

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