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Information by Geographic Area - Summary of Physical Location of Property, Plant and Equipment (Detail) - EUR (€) € in Millions | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
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Disclosure of property plant and equipment reported based on physical location of assets [line items] |  |  |
Property, plant and equipment | € 1,517 | € 1,477 | € 1,255
United States [member] |  |  |
Disclosure of property plant and equipment reported based on physical location of assets [line items] |  |  |
Property, plant and equipment | 681 | 729 |
France [member] |  |  |
Disclosure of property plant and equipment reported based on physical location of assets [line items] |  |  |
Property, plant and equipment | 586 | 543 |
Germany [member] |  |  |
Disclosure of property plant and equipment reported based on physical location of assets [line items] |  |  |
Property, plant and equipment | 156 | 134 |
Czech Republic [member] |  |  |
Disclosure of property plant and equipment reported based on physical location of assets [line items] |  |  |
Property, plant and equipment | 65 | 45 |
Other countries [member] |  |  |
Disclosure of property plant and equipment reported based on physical location of assets [line items] |  |  |
Property, plant and equipment | € 29 | € 26 |

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- Definition Disclosure of property plant and equipment reported based on physical location of assets. + 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 2017-01-01 -Paragraph 73 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=16&date=2017-03-01&anchor=para_73_e&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 54 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_54_a&doctype=Standard -URIDate 2017-03-09 + Details
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