Tangible asset (Details) - EUR (€) € in Millions	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Property, plant and equipment [abstract]
Acquisitions through business combinations, property, plant and equipment	€ 2,538	€ 4,053
Disposals, property, plant and equipment	848	1,004
Gains (losses) on disposals of property, plant and equipment	27	€ 30
Right-of-use assets	€ 4,541		€ 5,051

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2019-01-01
-Paragraph 73
-Subparagraph e
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e_iii&doctype=Standard
-URIDate 2019-03-27

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 16
-IssueDate 2019-01-01
-Paragraph 73
-Subparagraph e
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=16&code=ifrs-tx-2019-en-r&anchor=para_73_e_ii&doctype=Standard
-URIDate 2019-03-27

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- Definition

The gains (losses) on disposals of property, plant and equipment. [Refer: Property, plant and equipment]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2019-01-01
-Paragraph 98
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_98_c&doctype=Standard
-URIDate 2019-03-27

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- References

No definition available.

+ Details

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- Definition

The amount of assets that represent a lessee's right to use an underlying asset for the lease term. Underlying asset is an asset that is the subject of a lease, for which the right to use that asset has been provided by a lessor to a lessee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2019-01-01
-Paragraph 53
-Subparagraph j
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2019-en-r&anchor=para_53_j&doctype=Standard
-URIDate 2019-03-27

+ Details

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