Statement Of Financial Position [Abstract]
| Concept |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | ||||||||||||||||||
| Assets [abstract] | ||||||||||||||||||
| Non-current assets [abstract] | ||||||||||||||||||
| Property, plant and equipment | — |
20 1.4
GBP
|
— | — | — | — |
1 8 7. 1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — |
1 6.5
GBP
|
— | — | — | — |
9,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-current assets | — |
235,600,000
GBP
|
— | — | — | — |
20 7 .1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current assets [abstract] | ||||||||||||||||||
| Current inventories | — |
32,800,000
GBP
|
— | — | — | — |
33,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other current receivables | — |
3 9.1
GBP
|
— | — | — | — |
35. 7
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — |
41,500,000
GBP
|
— | — | — | — |
3 1.5
GBP
|
— | — | — | — | — | — | — | — |
26,600,000
GBP
|
— | — |
| Current assets | — |
1 14.4
GBP
|
— | — | — | — |
1 00.8
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Assets | — |
350,000,000
GBP
|
— | — | — | — |
3 0 7. 9
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||
| Issued capital | — |
2,300,000
GBP
|
— | — | — | — |
2,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Retained earnings | — |
21 3.4
GBP
|
— | — | — | — |
1 62.3
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Treasury shares | — |
4,600,000
GBP
|
— | — | — | — |
2,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Other reserves | — |
23,900,000
GBP
|
— | — | — | — |
4 1.5
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity |
4,600,000
GBP
|
234,800,000
GBP
|
213,400,000
GBP
|
200,000
GBP
|
23,900,000
GBP
|
2,300,000
GBP
|
204,100,000
GBP
|
2,300,000
GBP
|
1 62.3
GBP
|
–
GBP
|
2,000,000
GBP
|
4 1.5
GBP
|
–
GBP
|
1 57 .8
GBP
|
–
GBP
|
156,200,000
GBP
|
3,600,000
GBP
|
2,000,000
GBP
|
| Liabilities [abstract] | ||||||||||||||||||
| Non-current liabilities [abstract] | ||||||||||||||||||
| Non-current provisions [abstract] | ||||||||||||||||||
| Non-current provisions | — |
9. 7
GBP
|
— | — | — | — |
9,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — |
2. 7
GBP
|
— | — | — | — |
900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-current liabilities | — |
24,400,000
GBP
|
— | — | — | — |
3 1.1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current liabilities [abstract] | ||||||||||||||||||
| Current provisions [abstract] | ||||||||||||||||||
| Current provisions | — |
9,900,000
GBP
|
— | — | — | — |
5,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other current payables | — |
75,600,000
GBP
|
— | — | — | — |
63,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current liabilities | — |
90,800,000
GBP
|
— | — | — | — |
7 2. 7
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Liabilities | — |
1 15.2
GBP
|
— | — | — | — |
1 03.8
GBP
|
— | — | — | — | — | — | — | — | — | — | — |