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Revenue - Disclosure of geographical areas (Detail) - EUR (€) € in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of geographical areas [line items] |  |  |
Revenue | € 5,686 | € 5,237 | € 4,743
France [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 554 | 557 | 493
Germany [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 1,339 | 1,217 | 1,042
United Kingdom [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 175 | 188 | 203
Switzerland [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 77 | 123 | 86
Other Europe [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 1,038 | 940 | 798
United States [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 1,897 | 1,691 | 1,511
Canada [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 107 | 78 | 68
Asia and Other Pacific [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | 300 | 270 | 292
Other countries [member] |  |  |
Disclosure of geographical areas [line items] |  |  |
Revenue | € 199 | € 173 | € 250

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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. + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 28 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_28_a&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 23 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_23_a&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 32 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_32&doctype=Standard -URIDate 2018-03-16 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 33 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_33_a&doctype=Standard -URIDate 2018-03-16 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 34 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_34&doctype=Standard -URIDate 2018-03-16 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 82 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_82_a&doctype=Standard -URIDate 2018-03-16 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 103 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_103&doctype=Standard -URIDate 2018-03-16 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_102&doctype=Standard -URIDate 2018-03-16 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 5 -IssueDate 2018-01-01 -Paragraph 33 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=5&date=2018-03-01&anchor=para_33_b_i&doctype=Standard -URIDate 2018-03-16 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2018-01-01 -Paragraph B12 -Subparagraph b -Clause v -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B12_b_v&doctype=Appendix&seq=2 -URIDate 2018-03-16 Reference 11: http://www.xbrl.org/2003/role/exampleRef -Name IFRS -Number 12 -IssueDate 2018-01-01 -Paragraph B10 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2018-03-01&anchor=para_B10_b&doctype=Appendix&seq=2 -URIDate 2018-03-16 + Details
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