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CURRENCY GAINS / (LOSSES) - Foreign Currency Translation Reserve (Details) - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Movement in foreign currency translation reserve [abstract] |  |
Foreign currency translation reserve at January 1 | € 4 | € 3
Effect of currency translation differences | (17) | 1
Foreign currency translation reserve at December 31 | € (13) | € 4

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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 2020-01-01 -Paragraph 91 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_91_b&doctype=Standard -URIDate 2020-01-01 + 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 2020-01-01 -Paragraph 52 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2020-en-r&anchor=para_52_b&doctype=Standard -URIDate 2020-01-01 + Details
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