Investments - Summary of Investments in Real Estate (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about investment property [abstract]
Beginning balance	€ 2,147	€ 1,999
Additions	472	239
Subsequent expenditure capitalized	3	10
Transfers from other headings		1
Disposals	(209)	(202)
Fair value gains / (losses)	261	193
Net exchange differences	27	(89)
Other	(1)	(4)
Ending balance	€ 2,700	€ 2,147

Transfer from other headings investment property.

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- Definition

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

+ References

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

+ References

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- References

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

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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]

+ References

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The increase (decrease) in investment property resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Investment property]

+ References

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- Definition

Expiry date 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee under a finance lease) 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. Effective 2019-01-01: 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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