Issued capital and reserves - Share capital (Details) - EUR (€) € / shares in Units, € in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Issued capital and reserves
Beginning balance (shares)	10,000,000
Issue of shares-ordinary shares	300,000
Ending balance (shares)	10,300,000	10,000,000
Ordinary shares issued	256,410
Par value per share	€ 0.01	€ 0.01
Dividends paid	€ 10	€ 270
Dividends paid by subsidiary to non-controlling interest	7
Dividends paid to parent company	€ 3	€ 270

The amount of dividends paid by the entity on ordinary shares. [Refer: Ordinary shares [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 34
-IssueDate 2017-01-01
-Paragraph 16A
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=34&date=2017-03-01&anchor=para_16A_f&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_DividendsPaidOrdinaryShares
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for dividends paid to equity holders of the parent, classified as financing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2017-01-01
-Paragraph 17
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2017-03-01&anchor=para_17&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_DividendsPaidToEquityHoldersOfParentClassifiedAsFinancingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for dividends paid to non-controlling interests, classified as financing activities. [Refer: Non-controlling interests; Dividends paid to non-controlling interests]

+ References

+ Details

Name:	ifrs-full_DividendsPaidToNoncontrollingInterestsClassifiedAsFinancingActivities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

The increase (decrease) in the number of shares outstanding. [Refer: Number of shares outstanding]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 79
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a_iv&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_IncreaseDecreaseInNumberOfSharesOutstanding
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of shares issued by the entity, for which full payment has been received.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 79
-Subparagraph a
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a_ii&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_NumberOfSharesIssuedAndFullyPaid
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares that have been authorised and issued, reduced by treasury shares held. [Refer: Treasury shares]

+ References

+ Details

Name:	ifrs-full_NumberOfSharesOutstanding
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The nominal value per share.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 79
-Subparagraph a
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_79_a_iii&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_ParValuePerShare
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant