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Deferred Income Taxes - Components of Non Recognized Deferred Tax Assets (Detail) - EUR (€) € in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Significant components of deferred tax assets and liabilities [line items] |  |
Tax losses | € 1,393 | € 1,345
Total | (356) | (428)
Unused tax losses [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Tax losses | (183) | (164)
Long-term assets [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Deductible temporary differences | (116) | (193)
Pensions [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Deductible temporary differences | (20) | (25)
Other temporary differences [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Deductible temporary differences | (37) | (46)
Temporary differences [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Deductible temporary differences | (173) | (264)
Expiring in 2018 to 2021 [member] | Unused tax losses [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Tax losses | (22) | (13)
Expiring in 2022 and after limited [member] | Unused tax losses [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Tax losses | (143) | (132)
Unlimited [member] | Unused tax losses [member] |  |
Significant components of deferred tax assets and liabilities [line items] |  |
Tax losses | € (18) | € (19)

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- Definition The amount of deductible temporary differences for which no deferred tax asset is recognised in the statement of financial position. [Refer: Temporary differences [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 12 -IssueDate 2017-01-01 -Paragraph 81 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=12&date=2017-03-01&anchor=para_81_e&doctype=Standard -URIDate 2017-03-09 + Details
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