Provisions for Retirement Benefit Obligations - Change in net provision (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Provisions for Retirement Benefit Obligations
Provision at beginning of period	€ (1,127)	€ (1,029)	€ (866)
Expense for the period	(209)	(1)	(194)
Actuarial gains or losses recognized in other comprehensive income	(49)	(96)	31
Provision at end of period	€ (1,385)	€ (1,127)	€ (1,029)

No definition available.

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- Definition

The amount of non-current provisions for employee benefits. [Refer: Provisions for employee benefits]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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+ Details

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- Definition

The amount of other comprehensive income, net of tax, related to gains (losses) on remeasurements of defined benefit plans, which comprise actuarial gains and losses; the return on plan assets, excluding amounts included in net interest on the net defined benefit liability (asset); and any change in the effect of the asset ceiling, excluding amounts included in net interest on the net defined benefit liability (asset). [Refer: Other comprehensive income; Defined benefit plans [member]; Plan assets [member]; Net defined benefit liability (asset)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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- Definition

The amount of post-employment benefit expense relating to defined benefit plans. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2020-01-01
-Paragraph 5
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+ Details

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