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Financial Risk Management - Summary of Exposure to Financial Counterparties by Rating Type (Detail) € in Millions	Dec. 31, 2017 EUR (€) Counterparty	Dec. 31, 2016 EUR (€) Counterparty
Disclosure of nature and extent of risks arising from financial instruments [line items]
Number of financial counterparties | Counterparty	18	15
Exposure | €	€ 295	€ 398
Rated Aa or better [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Number of financial counterparties | Counterparty	3	3
Exposure | €	€ 52	€ 13
Rated A [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Number of financial counterparties | Counterparty	12	9
Exposure | €	€ 224	€ 369
Rated Baa [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Number of financial counterparties | Counterparty	3	3
Exposure | €	€ 19	€ 16

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- Definition

Number of financial counterparties.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 35K
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35K_a&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 36
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_36_a&doctype=Standard&book=B
-URIDate 2017-03-09

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