Provisions for retirement benefit obligations - Breakdown of expense recognized for the year (Details) - EUR (€) € in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Provisions for retirement benefit obligations
Service cost for the period	€ (211)	€ (183)	€ (237)
Interest cost for the period	(50)	(46)	(14)
Benefits for the period			21
Total	€ (261)	€ (228)	€ (230)

The expense of employee service in the current period arising from defined benefit plans. [Refer: Post-employment benefit expense in profit or loss, defined benefit plans] [Contrast: Increase in net defined benefit liability (asset) resulting from current service cost]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 135
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_135_b&doctype=Standard
-URIDate 2024-03-27

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

The amount of interest expense arising from defined benefit plans. [Refer: Interest expense; Post-employment benefit expense in profit or loss, defined benefit plans] [Contrast: Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)]

+ References

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of expense (income) resulting from past service cost and losses (gains) arising from settlements. [Refer: Post-employment benefit expense in profit or loss, defined benefit plans; Past service cost, defined benefit plans] [Contrast: Increase (decrease) in net defined benefit liability (asset) resulting from past service cost and losses (gains) arising from settlements]

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The amount of post-employment benefit expense included in profit or loss relating to defined benefit plans. [Refer: Profit (loss); Defined benefit plans [domain]] [Contrast: Increase (decrease) in net defined benefit liability (asset) resulting from expense (income) in profit or loss]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 5
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_5&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 135
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_135_b&doctype=Standard
-URIDate 2024-03-27

+ Details

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Namespace Prefix:	ifrs-full_
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Balance Type:	debit
Period Type:	duration