Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2023-12-31 |
As at 2022-12-31 |
As at 2021-12-31 |
As at 2020-12-31 |
|---|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | ||||
| Property, plant and equipment [abstract] | ||||
| Land and buildings [abstract] | ||||
| Land and buildings |
63,479,000
EUR
|
69,677,000
EUR
|
78,602,000
EUR
|
— |
| Other property, plant and equipment |
89,947,000
EUR
|
53,181,000
EUR
|
48,285,000
EUR
|
— |
| Intangible assets and goodwill [abstract] | ||||
| Intangible assets other than goodwill [abstract] | ||||
| Intangible assets other than goodwill |
12,026,000
EUR
|
19,251,000
EUR
|
17,427,000
EUR
|
— |
| Goodwill |
105,612,000
EUR
|
105,612,000
EUR
|
105,612,000
EUR
|
— |
| Miscellaneous non-current assets [abstract] | ||||
| Other non-current assets |
4,335,000
EUR
|
5,819,000
EUR
|
6,849,000
EUR
|
— |
| Trade and other current receivables [abstract] | ||||
| Current trade receivables |
208,567,000
EUR
|
194,643,000
EUR
|
156,977,000
EUR
|
— |
| Other current receivables |
14,458,000
EUR
|
14,509,000
EUR
|
16,211,000
EUR
|
— |
| Current prepayments and current accrued income including current contract assets [abstract] | ||||
| Current prepayments and current accrued income including current contract assets |
10,895,000
EUR
|
11,383,000
EUR
|
12,293,000
EUR
|
— |
| Classes of current inventories [abstract] | ||||
| Current inventories |
231,521,000
EUR
|
245,714,000
EUR
|
175,496,000
EUR
|
— |
| Classes of current inventories, alternative [abstract] | ||||
| Cash and cash equivalents [abstract] | ||||
| Cash and cash equivalents |
286,077,000
EUR
|
305,915,000
EUR
|
351,571,000
EUR
|
235,402,000
EUR
|
| Miscellaneous current assets [abstract] | ||||
| Current investments |
4,670,000
EUR
|
1,651,000
EUR
|
2,763,000
EUR
|
— |
| Classes of other provisions [abstract] | ||||
| Other provisions [abstract] | ||||
| Other current provisions |
10,284,000
EUR
|
9,325,000
EUR
|
8,537,000
EUR
|
— |
| Borrowings [abstract] | ||||
| Non-current portion of non-current borrowings |
32,217,000
EUR
|
32,335,000
EUR
|
34,366,000
EUR
|
— |
| Current borrowings and current portion of non-current borrowings [abstract] | ||||
| Current borrowings |
5,095,000
EUR
|
-
EUR
|
-
EUR
|
— |
| Current portion of non-current borrowings |
12,288,000
EUR
|
11,217,000
EUR
|
10,218,000
EUR
|
— |
| Non-current portion of non-current borrowings, by type [abstract] | ||||
| Trade and other current payables [abstract] | ||||
| Current trade payables |
89,350,000
EUR
|
121,920,000
EUR
|
113,979,000
EUR
|
— |
| Current accruals and current deferred income including current contract liabilities [abstract] | ||||
| Current deferred income including current contract liabilities [abstract] | ||||
| Current contract liabilities [abstract] | ||||
| Current advances received, representing current contract liabilities for performance obligations satisfied at point in time |
40,613,000
EUR
|
51,183,000
EUR
|
54,105,000
EUR
|
— |
| Current accruals and current deferred income including current contract liabilities |
7,745,000
EUR
|
11,155,000
EUR
|
14,823,000
EUR
|
— |
| Miscellaneous non-current liabilities [abstract] | ||||
| Other non-current liabilities |
54,374,000
EUR
|
44,524,000
EUR
|
48,860,000
EUR
|
— |
| Miscellaneous current liabilities [abstract] | ||||
| Other current liabilities |
7,034,000
EUR
|
5,412,000
EUR
|
5,036,000
EUR
|
— |
| Net assets (liabilities) [abstract] | ||||
| Assets |
1,159,415,000
EUR
|
1,147,405,000
EUR
|
1,104,249,000
EUR
|
— |
| Net current assets (liabilities) [abstract] | ||||
| Current assets |
756,188,000
EUR
|
773,815,000
EUR
|
715,311,000
EUR
|
— |
| Current liabilities |
242,822,000
EUR
|
273,338,000
EUR
|
251,211,000
EUR
|
— |
| Assets less current liabilities [abstract] |