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Provisions for employee benefits (Details 3) - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Other comprehensive income [Member] |  |
Remeasurements |  |
Actuarial (gains)/losses due to changes in demographic assumptions | € (14) | € (4)
Actuarial (gains)/losses due to changes in financial assumptions | 66 | 40
Experience (gains) losses | (5) | (10)
Return on plan assets | (12) | (42)
Gain (loss) on remeasurement, net defined benefit liability (asset) | 35 | (16)
TFR [Member] |  |
Remeasurements |  |
Actuarial (gains)/losses due to changes in demographic assumptions |  | (2)
Actuarial (gains)/losses due to changes in financial assumptions | (5) | 11
Experience (gains) losses | (1) | 10
Gain (loss) on remeasurement, net defined benefit liability (asset) | (6) | 19
Foreign defined benefit plans [Member] |  |
Remeasurements |  |
Actuarial (gains)/losses due to changes in demographic assumptions | (14) | (2)
Actuarial (gains)/losses due to changes in financial assumptions | 71 | 30
Experience (gains) losses | (3) | (6)
Return on plan assets | (12) | (42)
Gain (loss) on remeasurement, net defined benefit liability (asset) | 42 | (20)
FISDE and other foreign medical plans [Member] |  |
Remeasurements |  |
Actuarial (gains)/losses due to changes in demographic assumptions |  | (1)
Actuarial (gains)/losses due to changes in financial assumptions |  | (2)
Experience (gains) losses | (1) | (14)
Gain (loss) on remeasurement, net defined benefit liability (asset) | € (1) | (17)
Other benefit plans [Member] |  |
Remeasurements |  |
Actuarial (gains)/losses due to changes in demographic assumptions |  | 1
Actuarial (gains)/losses due to changes in financial assumptions |  | 1
Gain (loss) on remeasurement, net defined benefit liability (asset) |  | € 2

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- Definition The amount of gain/loss from experience on defined benefit plan. + References No definition available. + 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 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 2017-01-01 -Paragraph 141 -Subparagraph c -Clause ii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_c_ii&doctype=Standard -URIDate 2017-03-09 + 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 2017-01-01 -Paragraph 141 -Subparagraph c -Clause iii -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_c_iii&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from the remeasurement of that net defined benefit liability (asset). [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 c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_c&doctype=Standard -URIDate 2017-03-09 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets. 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]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2017-01-01 -Paragraph 141 -Subparagraph c -Clause i -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=19&date=2017-03-01&anchor=para_141_c_i&doctype=Standard -URIDate 2017-03-09 + Details
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