Income Tax - Summary of Deferred Tax Reconciliation to Balance Sheet (Details) - EUR (€) € in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred Tax Assets And Liabilities [Abstract]
Deferred tax assets	€ 8	€ 9
Deferred tax liabilities	€ 2	€ 3

The amounts of income taxes recoverable in future periods in respect of: (a) deductible temporary differences; (b) the carryforward of unused tax losses; and (c) the carryforward of unused tax credits. [Refer: Temporary differences [member]; Unused tax credits [member]; Unused tax losses [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 12
-IssueDate 2017-01-01
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-Subparagraph g
-Clause i
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-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2017-01-01
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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_56&doctype=Standard
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