Provisions for Retirement Benefit Obligations - Change in net provision (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Provisions for Retirement Benefit Obligations
At beginning of period	€ (1,385)	€ (1,127)	€ (1,029)
Other changes	(75)
Expense for the period	(200)	(209)	(1)
Actuarial gains or losses recognized in other comprehensive income	82	(49)	(96)
At end of period	€ (1,429)	€ (1,385)	€ (1,127)

No definition available.

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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 2021-01-01
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-URIDate 2021-03-24

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- Definition

The increase (decrease) in the net defined benefit liability (asset) resulting from expense (income) included in profit or loss. [Refer: Net defined benefit liability (asset); Profit (loss)] [Contrast: Post-employment benefit expense in profit or loss, defined benefit plans]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
-Paragraph 141
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- Definition

The increase (decrease) in the net defined benefit liability (asset) resulting from changes that the entity does not separately disclose in the same statement or note. [Refer: Net defined benefit liability (asset)]

+ References

+ Details

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- Definition

The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 19
-IssueDate 2021-01-01
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