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FINANCIAL RISK MANAGEMENT - Mark-to-market Movements Recognized in Other Gains (Losses) - Net (Details) - Commodity price risk - 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 (losses) / gains on commodity derivatives - net | € (31) | € (56) | € 7
Unrealized gains / (losses) on commodity derivatives - net | € 25 | € 31 | € (83)

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- Definition Realized gains losses on commodity derivatives net. + References No definition available. + Details
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- Definition Unrealized gains losses on commodity derivatives net. + References No definition available. + Details
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- Details
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