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 |
22,500,000
GBP
|
— | — | — | — | — |
2 4.3
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets |
45. 1
GBP
|
— | — | — | — | — |
4 7. 0
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Investment property |
1,200,000
GBP
|
— | — | — | — | — |
1,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other non-current receivables |
1,000,000
GBP
|
— | — | — | — | — |
3 .1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets |
10,500,000
GBP
|
— | — | — | — | — |
10,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-current assets |
290,300,000
GBP
|
— | — | — | — | — |
290. 1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current assets [abstract] | ||||||||||||||||||
| Current inventories |
1,500,000
GBP
|
— | — | — | — | — |
1,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other current receivables |
117 .4
GBP
|
— | — | — | — | — |
76,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents |
261,600,000
GBP
|
— | — | — | — | — |
17 3.4
GBP
|
— | — | — | — | — | — | — | — | — |
175,700,000
GBP
|
— |
| Current assets |
391,800,000
GBP
|
— | — | — | — | — |
282,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||
| Issued capital |
7. 6
GBP
|
— | — | — | — | — |
7. 6
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Retained earnings |
245,300,000
GBP
|
— | — | — | — | — |
211,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Other reserves |
104,000,000
GBP
|
— | — | — | — | — |
104,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent |
356,900,000
GBP
|
— | — | — | — | — |
324. 1
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-controlling interests |
4 .7
GBP
|
— | — | — | — | — |
4,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity |
361,600,000
GBP
|
245,300,000
GBP
|
104,000,000
GBP
|
356,900,000
GBP
|
4,700,000
GBP
|
7. 6
GBP
|
328,400,000
GBP
|
7. 6
GBP
|
211,900,000
GBP
|
4,300,000
GBP
|
104,600,000
GBP
|
32 4. 1
GBP
|
211,500,000
GBP
|
3 .1
GBP
|
158,400,000
GBP
|
377 .5
GBP
|
380 .6
GBP
|
7. 6
GBP
|
| Liabilities [abstract] | ||||||||||||||||||
| Non-current liabilities [abstract] | ||||||||||||||||||
| Non-current provisions [abstract] | ||||||||||||||||||
| Non-current provisions |
1,600,000
GBP
|
— | — | — | — | — |
1,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other non-current payables |
2,700,000
GBP
|
— | — | — | — | — |
2,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities |
11. 0
GBP
|
— | — | — | — | — |
8,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-current liabilities |
63,200,000
GBP
|
— | — | — | — | — |
66,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current liabilities [abstract] | ||||||||||||||||||
| Current provisions [abstract] | ||||||||||||||||||
| Current provisions |
600,000
GBP
|
— | — | — | — | — |
500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other current payables |
235,400,000
GBP
|
— | — | — | — | — |
160,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current liabilities |
257 .3
GBP
|
— | — | — | — | — |
177 .4
GBP
|
— | — | — | — | — | — | — | — | — | — | — |