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Financial Risk Management - Summary of Impact on Profit and Equity (before tax effect) of a 10 % strengthening of the US Dollar versus the Euro for US Dollar functional currency (Detail) - 10% strengthening US Dollar/Euro [member] € in Millions	12 Months Ended
	Dec. 31, 2017 EUR (€)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Effect on profit before tax	€ (8)
Effect on pretax equity	€ 11

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- Definition

Foreign exchange sensitivity effect on pretax equity.

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- Definition

Foreign exchange sensitivity effect on profit before tax.

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No definition available.

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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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