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FINANCIAL RISK MANAGEMENT - Effect of Foreign Currency Derivatives Impacts and Financing Transaction Exposures (Details) - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Realized exchange (losses) / gains on foreign currency derivatives - net | € (11) | € 1 | € 11
Unrealized gains / (losses) on foreign currency derivatives - net | (8) | 1 | (3)
Total | (32) | 13 | 28
Currency risk | At Fair Value through Profit and loss |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Realized exchange (losses) / gains on foreign currency derivatives - net | 7 | 9 | 5
Unrealized gains / (losses) on foreign currency derivatives - net | (39) | 4 | 23
Total | € (32) | € 13 | € 28

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- Definition Realized gains (losses) on foreign currency derivatives - net. + References No definition available. + Details
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- Definition Unrealized gains (losses) on foreign currency derivatives - net. + References No definition available. + Details
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