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Financial Risk Management - Summary of Mark-to-market movements Recognized in Other Gains (Losses) - Net (Detail) - Commodity price risk [member] - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Realized gain / (loss) on commodity derivatives-net | € 7 | € 16 | € (16)
Unrealized (loss) / gain on commodity derivatives-net | € (83) | € 41 | € 31

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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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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Details
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