Related Party Transactions - Sales to and Purchases From Associates and Joint Ventures (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Joint ventures where entity is venturer [member]
Disclosure of transactions between related parties [line items]
Sales	€ 118	€ 107	€ 111
Purchases	24	31	55
Associates [member]
Disclosure of transactions between related parties [line items]
Sales	37	40	51
Purchases	€ 16	€ 193	€ 400

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

+ Details

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- Definition

The amount of goods purchased by the entity in related party transactions. [Refer: Related parties [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 24
-IssueDate 2019-01-01
-Paragraph 21
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=24&code=ifrs-tx-2019-en-r&anchor=para_21_a&doctype=Standard
-URIDate 2019-03-27

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- Definition

The amount of revenue arising from the sale of goods in related party transactions. [Refer: Revenue; Related parties [member]]

+ References

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- Details

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