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Summary of Significant Accounting Policies - Opening Balance Sheet Reclassification (IFRS 15 Standard) (Detail) - EUR (€) € in Millions	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017
Disclosure of reclassification of financial assets [line items]
Trade receivables and other		€ 483	€ 467
Trade payables and other		(1,023)	(984)
Provisions	€ (136)	(130)	€ (153)
Contracts liabilities reclassification [member]
Disclosure of reclassification of financial assets [line items]
Trade receivables and other		16
Trade payables and other		(39)
Provisions		€ 23

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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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The amount of provisions other than provisions for employee benefits. [Refer: Provisions]

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The amount of trade payables and other payables. [Refer: Trade payables; Other payables]

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The amount of trade receivables and other receivables. [Refer: Trade receivables; Other receivables]

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