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Information by Geographic Area - Summary of Physical Location of Property, Plant and Equipment (Detail) - EUR (€) € in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Property, plant and equipment | € 1,666 | € 1,517 | € 1,477
United States [member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Property, plant and equipment | 740 | 681 |
France [member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Property, plant and equipment | 613 | 586 |
Germany [member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Property, plant and equipment | 181 | 156 |
Czech Republic [member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Property, plant and equipment | 84 | 65 |
Other countries [member] |  |  |
Disclosure of detailed information about property, plant and equipment [line items] |  |  |
Property, plant and equipment | € 48 | € 29 |

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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 amount of tangible assets that: (a) are held for use in the production or supply of goods or services, for rental to others, or for administrative purposes; and (b) are expected to be used during more than one period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 16 -IssueDate 2018-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2018-03-01&anchor=para_73_e&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 54 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_54_a&doctype=Standard -URIDate 2018-03-16 + Details
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