EARNINGS PER SHARE - Earnings Attributable to Equity Holders of Parent used to Calculate Basic and Diluted Earnings per share (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings per share [abstract]
Earnings attributable to equity holders of the parent used to calculate basic and diluted earnings per share	€ 59	€ 188	€ (31)

The profit (loss) attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss)]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 33
-IssueDate 2019-01-01
-Paragraph 70
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=33&code=ifrs-tx-2019-en-r&anchor=para_70_a&doctype=Standard
-URIDate 2019-03-27

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