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Financial Risk Management - Summary of Impact on Profit and Equity (Before Tax Effect) of a 10 % Strengthening of US Dollar Versus Euro for Non US Dollar Functional Currency Entities (Parenthetical) (Detail) € in Millions	12 Months Ended
	Dec. 31, 2018 EUR (€)
Derivatives on commercial transaction [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Effect on pretax equity	€ (34)

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- Definition

Foreign exchange sensitivity on commercial and financing transactions exposures effect on pretax equity.

+ References

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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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