Equity - Retained Earnings (Details) - EUR (€)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Disclosure of classes of share capital [line items]
Increase (decrease) through appropriation of retained earnings	€ 6,000,000	€ 8,000,000	€ 8,000,000
Revaluation reserve	78,000,000	85,000,000
Reserve for cancelled share capital	0	75,000,000
Capital redemption reserve	€ 731,000,000	€ 731,000,000

A component of equity representing the reserve for the redemption of the entity's own shares.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
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-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
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Period Type:	instant

- 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 increase (decrease) in equity resulting from transfers between a revaluation surplus and retained earnings. [Refer: Retained earnings; Revaluation surplus]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_106_d&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Definition

A component of equity representing the accumulated revaluation surplus on the revaluation of assets recognised in other comprehensive income. [Refer: Other comprehensive income]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 38
-IssueDate 2017-01-01
-Paragraph 85
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=38&date=2017-03-01&anchor=para_85&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2017-03-01&anchor=para_39&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Definition

Cancelled Share Capital Reserve

+ References

No definition available.

+ Details

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