Property, Plant and Equipment - Composition of and Movement in Net Property, Plant and Equipment (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Reconciliation of changes in property, plant and equipment [abstract]
Property, plant and equipment	€ 36,393	€ 33,910
Additions	6,879	7,248
Depreciation	(5,953)	(5,951)
Disposals	(22)	(89)
Transfers and others	(413)	(359)
Translation differences and hyperinflation adjustments	(2,772)	1,661
Inclusion of companies	113
Exclusion of companies		(27)
Property, plant and equipment	34,225	36,393
Land and buildings
Reconciliation of changes in property, plant and equipment [abstract]
Property, plant and equipment	4,858	4,851
Additions	64	59
Depreciation	(391)	(386)
Disposals	(14)	(36)
Transfers and others	139	198
Translation differences and hyperinflation adjustments	(293)	173
Inclusion of companies	20
Exclusion of companies		(1)
Property, plant and equipment	4,383	4,858
Plant and machinery
Reconciliation of changes in property, plant and equipment [abstract]
Property, plant and equipment	26,770	24,682
Additions	2,096	1,325
Depreciation	(5,062)	(5,034)
Disposals	4	(22)
Transfers and others	3,455	4,464
Translation differences and hyperinflation adjustments	(2,039)	1,369
Inclusion of companies	73
Exclusion of companies		(14)
Property, plant and equipment	25,297	26,770
Furniture, tools and other items
Reconciliation of changes in property, plant and equipment [abstract]
Property, plant and equipment	1,426	1,412
Additions	223	190
Depreciation	(500)	(531)
Disposals	(4)	(19)
Transfers and others	230	344
Translation differences and hyperinflation adjustments	(117)	30
Inclusion of companies	9
Exclusion of companies		0
Property, plant and equipment	1,267	1,426
PP&E in progress
Reconciliation of changes in property, plant and equipment [abstract]
Property, plant and equipment	3,339	2,965
Additions	4,496	5,674
Depreciation	0	0
Disposals	(8)	(12)
Transfers and others	(4,237)	(5,365)
Translation differences and hyperinflation adjustments	(323)	89
Inclusion of companies	11
Exclusion of companies		(12)
Property, plant and equipment	€ 3,278	€ 3,339

The increase in property, plant and equipment resulting from acquisitions through business combinations. [Refer: Business combinations [member]; Property, plant and equipment]

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The amount of additions to property, plant and equipment other than those acquired through business combinations. [Refer: Business combinations [member]; Property, plant and equipment]

+ References

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The amount of depreciation of property, plant and equipment. [Refer: Depreciation and amortisation expense; Property, plant and equipment]

+ References

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The decrease in property, plant and equipment resulting from disposals. [Refer: Property, plant and equipment]

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The increase (decrease) in property, plant and equipment 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: Property, plant and equipment]

+ References

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The increase (decrease) in property, plant and equipment resulting from transfers and changes that the entity does not separately disclose in the same statement or note. [Refer: Property, plant and equipment]

+ References

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The amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period.

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Increase (Decrease) In Property, Plant And Equipment From Inclusion Or Exclusion Of Companies

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