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Other Gains / (Losses) - Net - Summary of Other Gains/(Losses) Net (Detail) - EUR (€) € in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Analysis of income and expense [abstract] |  |  |  |
Realized gains / (losses) on derivatives(A) | € 15 | € 5 | € 22 | € (3)
Unrealized gains / (losses) on derivatives at fair value through profit and loss-net(A) | 11 | (10) | (43) | 18
Unrealized exchange (losses) / gains from the remeasurement of monetary assets and liabilities-net |  | (1) | 1 | (5)
Gains on pension plan amendments(B) |  |  |  | 22
Losses on disposal | (3) | (1) | (4) | (2)
Other | 1 |  | 1 | 1
Total other gains / (losses)-net | € 24 | € (7) | € (23) | € 31

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- Definition Unrealized exchange gains / (losses) from the remeasurement of monetary assets and liabilities, net. + References No definition available. + Details
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- Definition Unrealized gains (losses) on change in fair value of derivatives. + References No definition available. + Details
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- References No definition available. + Details
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- Definition The gains (losses) on disposals of non-current assets. [Refer: Non-current assets] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_112_c&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The gains (losses) that the entity does not separately disclose in the same statement or note. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 102 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_102&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 103 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_103&doctype=Standard -URIDate 2017-03-09 + Details
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