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Revenue - Disclosure of geographical areas (Detail) - EUR (€) € in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disclosure of geographical areas [line items]
Revenue	€ 1,538	€ 1,474	€ 3,074	€ 2,860
France [member]
Disclosure of geographical areas [line items]
Revenue	154	152	306	302
Germany [member]
Disclosure of geographical areas [line items]
Revenue	339	349	678	700
United Kingdom [member]
Disclosure of geographical areas [line items]
Revenue	49	39	99	83
Switzerland [member]
Disclosure of geographical areas [line items]
Revenue	18	26	38	43
Other Europe [member]
Disclosure of geographical areas [line items]
Revenue	286	270	555	514
United States [member]
Disclosure of geographical areas [line items]
Revenue	600	485	1,164	928
Canada [member]
Disclosure of geographical areas [line items]
Revenue	9	28	27	49
Asia and Other Pacific [member]
Disclosure of geographical areas [line items]
Revenue	68	76	137	143
Other countries [member]
Disclosure of geographical areas [line items]
Revenue	€ 15	€ 49	€ 70	€ 98

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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

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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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