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Revenue - Disclosure of geographical areas (Detail) - EUR (€) € in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disclosure of geographical areas [line items]
Revenue	€ 1,474	€ 1,382	€ 2,860	€ 2,710
France [member]
Disclosure of geographical areas [line items]
Revenue	152	151	302	293
Germany [member]
Disclosure of geographical areas [line items]
Revenue	349	310	700	607
United Kingdom [member]
Disclosure of geographical areas [line items]
Revenue	39	53	83	100
Switzerland [member]
Disclosure of geographical areas [line items]
Revenue	26	31	43	61
Other Europe [member]
Disclosure of geographical areas [line items]
Revenue	270	261	514	502
United States [member]
Disclosure of geographical areas [line items]
Revenue	485	442	928	880
Canada [member]
Disclosure of geographical areas [line items]
Revenue	28	25	49	44
Asia and Other Pacific [member]
Disclosure of geographical areas [line items]
Revenue	76	65	143	135
Other countries [member]
Disclosure of geographical areas [line items]
Revenue	€ 49	€ 44	€ 98	€ 88

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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.

+ References

No definition available.

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The income arising in the course of an entity's ordinary activities. Income is increases in economic benefits during the accounting period in the form of inflows or enhancements of assets or decreases of liabilities that result in an increase in equity, other than those relating to contributions from equity participants.

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