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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
	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.

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Unrealized gains losses on commodity derivatives net.

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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.

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No definition available.

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