Notes to the statement of financial position - Pension provisions and post-retirement benefits, sensitivity analysis for assumptions (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Discount Rate \| Bottom of range
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity level	1.40%	1.40%
Impact on defined benefit obligation	€ (5,515)	€ (5,708)
Discount Rate \| Top of range
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity level	2.40%	2.40%
Impact on defined benefit obligation	€ 4,751	€ 4,896
Pension Trend \| Bottom of range
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity level	1.00%	1.00%
Impact on defined benefit obligation	€ 7,179	€ 6,954
Pension Trend \| Top of range
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity level	2.00%	2.00%
Impact on defined benefit obligation	€ (7,931)	€ (7,715)
Mortality
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity level, basis spread on mortality rate	2 years	2 years
Impact on defined benefit obligation	€ (3,444)	€ (3,435)

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- Definition

The increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [Refer: Actuarial assumptions [member]]

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2017-01-01
-Paragraph 145
-Subparagraph a
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-URIDate 2017-03-09

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- Definition

The reasonably possible percentage of the increase in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]]

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Basis Spread On Mortality Rate

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