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Pensions and Other Post-employment Benefit Obligations - Summary of Amounts Recognized in Unaudited Interim Consolidated Income Statement (Detail) - Consolidated Income Statement [member] - EUR (€) € in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Disclosure of changes in financial position [line items] |  |  |  |
Current service cost | € (5) | € (7) | € (11) | € (13)
Past service cost | 0 | 0 | 0 | 22
Net interest | (4) | (4) | (8) | (9)
Immediate recognition of gains / (losses) arising over the period | 0 | 0 | 0 | 0
Administrative expenses | (1) | 0 | (1) | (1)
Total | (10) | (11) | (20) | (1)
Pension benefits [member] |  |  |  |
Disclosure of changes in financial position [line items] |  |  |  |
Current service cost | (3) | (4) | (8) | (9)
Past service cost | 0 | 0 | 0 | 18
Net interest | (2) | (2) | (4) | (4)
Immediate recognition of gains / (losses) arising over the period | 0 | 0 | 0 | 0
Administrative expenses | (1) | 0 | (1) | (1)
Total | (6) | (6) | (13) | 4
Other benefits [member] |  |  |  |
Disclosure of changes in financial position [line items] |  |  |  |
Current service cost | (2) | (3) | (3) | (4)
Past service cost | 0 | 0 | 0 | 4
Net interest | (2) | (2) | (4) | (5)
Immediate recognition of gains / (losses) arising over the period | 0 | 0 | 0 | 0
Total | € (4) | € (5) | € (7) | € (5)

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- Definition Actuarial gains (losses) arising from change in assumption recognized in profit loss. + References No definition available. + Details
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- Definition Defined benefit plan net periodic benefit cost. + References No definition available. + Details
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- Definition Disclosure of changes in financial position [line items] + References No definition available. + Details
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- Definition The amount of expenses that the entity classifies as being administrative. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2017-01-01 -Paragraph 35 -Subparagraph b -Clause vi -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=26&date=2017-03-01&anchor=para_35_b_vi&doctype=Standard -URIDate 2017-03-09 Reference 2: http://www.xbrl.org/2003/role/exampleRef -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 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2017-01-01 -Paragraph 99 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2017-03-01&anchor=para_99&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_a&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from the passage of time. [Refer: Interest expense; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_b&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_d&doctype=Standard -URIDate 2017-03-09 + Details
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