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Pensions and Other Post-employment Benefit Obligations - Details of Movement in Net Defined Benefit Obligations (Detail) - EUR (€) € in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Disclosure of net defined benefit liability (asset) [line items] |  |
Beginning balance | € 664 | € 735
Closing balance | 610 | 664
Consolidated Income Statement [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Current service cost | 24 | 24
Interest cost / (income) | 15 | 17
Past service cost | (36) | (20)
Immediate recognition of gains / (losses) arising over the year | 0 | 0
Administration expenses | 2 | 3
Statement of Comprehensive Income (Loss) [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
-actual return less interest on plan assets | 26 | (36)
-changes in financial assumptions | (45) | 37
-changes in demographic assumptions | (6) | (1)
-experience losses | (3) |
Effects of changes in foreign exchange rates | 15 | (48)
Consolidated Statement of Cash Flows [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Benefits paid | (23) | (23)
Contributions by the Group | (23) | (24)
Defined benefit obligations [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Beginning balance | 1,051 | 1,126
Closing balance | 990 | 1,051
Defined benefit obligations [member] | Consolidated Income Statement [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Current service cost | 24 | 24
Interest cost / (income) | 24 | 27
Past service cost | (36) | (20)
Immediate recognition of gains / (losses) arising over the year | 0 | 0
Defined benefit obligations [member] | Statement of Comprehensive Income (Loss) [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
-changes in financial assumptions | (45) | 37
-changes in demographic assumptions | (6) | (1)
-experience losses | (3) |
Effects of changes in foreign exchange rates | 31 | (90)
Defined benefit obligations [member] | Consolidated Statement of Cash Flows [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Benefits paid | (54) | (56)
Contributions by the plan participants | 4 | 4
Defined benefit obligations [member] | Pension benefits [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Beginning balance | 801 | 853
Closing balance | 789 | 801
Defined benefit obligations [member] | Pension benefits [member] | Consolidated Income Statement [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Current service cost | 18 | 18
Interest cost / (income) | 16 | 18
Past service cost |  | (16)
Immediate recognition of gains / (losses) arising over the year | 0 | 0
Defined benefit obligations [member] | Pension benefits [member] | Statement of Comprehensive Income (Loss) [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
-changes in financial assumptions | (30) | 23
-changes in demographic assumptions | (5) |
-experience losses | (1) |
Effects of changes in foreign exchange rates | 22 | (61)
Defined benefit obligations [member] | Pension benefits [member] | Consolidated Statement of Cash Flows [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Benefits paid | (35) | (38)
Contributions by the plan participants | 3 | 4
Defined benefit obligations [member] | Other benefits [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Beginning balance | 250 | 273
Closing balance | 201 | 250
Defined benefit obligations [member] | Other benefits [member] | Consolidated Income Statement [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Current service cost | 6 | 6
Interest cost / (income) | 8 | 9
Past service cost | (36) | (4)
Immediate recognition of gains / (losses) arising over the year | 0 | 0
Defined benefit obligations [member] | Other benefits [member] | Statement of Comprehensive Income (Loss) [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
-changes in financial assumptions | (15) | 14
-changes in demographic assumptions | (1) | (1)
-experience losses | (2) |
Effects of changes in foreign exchange rates | 9 | (29)
Defined benefit obligations [member] | Other benefits [member] | Consolidated Statement of Cash Flows [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Benefits paid | (19) | (18)
Contributions by the plan participants | 1 |
Plan Assets [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Beginning balance | (387) | (391)
Closing balance | (380) | (387)
Plan Assets [member] | Consolidated Income Statement [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Interest cost / (income) | (9) | (10)
Immediate recognition of gains / (losses) arising over the year | 0 | 0
Administration expenses | 2 | 3
Plan Assets [member] | Statement of Comprehensive Income (Loss) [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
-actual return less interest on plan assets | 26 | (36)
Effects of changes in foreign exchange rates | (16) | 42
Plan Assets [member] | Consolidated Statement of Cash Flows [member] |  |
Disclosure of net defined benefit liability (asset) [line items] |  |
Benefits paid | 31 | 33
Contributions by the Group | (23) | (24)
Contributions by the plan participants | € (4) | € (4)

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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c_ii&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph c -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c_iii&doctype=Standard -URIDate 2018-03-16 + 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 2018-01-01 -Paragraph 35 -Subparagraph b -Clause vi -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=26&date=2018-03-01&anchor=para_35_b_vi&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 103 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_103&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 99 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_99&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [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 2018-01-01 -Paragraph 141 -Subparagraph f -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_f&doctype=Standard -URIDate 2018-03-16 + 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 2018-01-01 -Paragraph 141 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_a&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of employer contributions to retirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2018-01-01 -Paragraph 35 -Subparagraph b -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=26&date=2018-03-01&anchor=para_35_b_i&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of increase (decrease) in the fair value measurement of liabilities due to a change in one or more unobservable inputs to reflect reasonably possible alternative assumptions. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 13 -IssueDate 2018-01-01 -Paragraph 93 -Subparagraph h -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=13&date=2018-03-01&anchor=para_93_h_ii&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from changes in foreign exchange rates. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_e&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The amount of income or expense arising from interest. [Refer: Interest expense; Interest income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 28 -Subparagraph e -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_28_e&doctype=Standard -URIDate 2018-03-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 23 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_23&doctype=Standard -URIDate 2018-03-16 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2018-01-01 -Paragraph 85 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_85&doctype=Standard -URIDate 2018-03-16 + 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 2018-01-01 -Paragraph 141 -Subparagraph d -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_d&doctype=Standard -URIDate 2018-03-16 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plans assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [member]; Interest expense (income), net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2018-01-01 -Paragraph 141 -Subparagraph c -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2018-03-01&anchor=para_141_c_i&doctype=Standard -URIDate 2018-03-16 + Details
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