Derivative Financial Instruments Schedule of Notional Amounts of Net Investment Hedges (Details) - EUR (€) € in Millions	Dec. 31, 2017	Dec. 31, 2016
Net Investment Hedging [Member] \| Foreign Currency Denominated Debt [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount of Nonderivative Instruments	€ 1,050	€ 850

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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