Financial assets and liabilities - Net external debt (Details) - EUR (€) € in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financial assets and liabilities
Loan notes	€ 8,392	€ 9,070
Term loan		627
Other borrowings	10	10
Total borrowings	8,402	9,707
Cash and cash equivalents	686	776	€ 554	€ 433
Derivative financial instruments used to hedge foreign currency and interest rate risk	251	0
Derivative financial instruments used to hedge foreign currency and interest rate risk	(6)	(124)
Net debt	€ 7,967	€ 8,807	€ 5,850

The amount of term loan facility.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_55&doctype=Standard
-URIDate 2017-03-09

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2017-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_45&doctype=Standard
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_i&doctype=Standard
-URIDate 2017-03-09

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of instruments issued by the entity that represent indebtedness.

+ References

+ Details

Name:	ifrs-full_DebtSecurities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of net debt of the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The amount of non-current derivative financial assets. [Refer: Derivative financial assets]

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The amount of non-current derivative financial liabilities. [Refer: Derivative financial liabilities]

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of borrowings that the entity does not separately disclose in the same statement or note. [Refer: Borrowings]

+ References

+ Details

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Balance Type:	credit
Period Type:	instant