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Currency Gains / (Losses) - Summary of Foreign Currency Translation Reserve (Detail) - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Movement in foreign currency translation reserve [abstract] |  |
Foreign currency translation reserve at January 1 | € (7) | € 12
Effect of currency translation differences | 10 | (19)
Foreign currency translation reserve at December 31 | € 3 | € (7)

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- Definition Movement in foreign currency translation reserve. + References No definition available. + Details
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- Definition The gains (losses) recognised in other comprehensive income on exchange differences on the translation of financial statements of foreign operations, before tax. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 91 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_91_b&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition A component of equity representing exchange differences on translation of financial statements of foreign operations recognised in other comprehensive income and accumulated in equity. [Refer: Other comprehensive income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 21 -IssueDate 2018-01-01 -Paragraph 52 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=21&date=2018-03-01&anchor=para_52_b&doctype=Standard -URIDate 2018-03-16 + Details
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