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 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 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-01-01 |
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 |
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 |
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 |
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 | — | — | — | — |
254,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
262,500,000
GBP
|
— |
273,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — | — | — | — |
50,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
52,700,000
GBP
|
— |
43,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — | — | — | — |
11,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
20,600,000
GBP
|
— |
15,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Non-current assets | — | — | — | — |
839,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
855,500,000
GBP
|
— |
836,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Current assets [abstract] | |||||||||||||||||||||||||||||||||||||||
| Current inventories | — | — | — | — |
128,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
102,600,000
GBP
|
— |
113,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Trade and other current receivables | — | — | — | — |
175,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
154,200,000
GBP
|
— |
166,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other current financial assets | — | — | — | — |
-
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
-
GBP
|
— |
6,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — | — |
136,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
135,800,000
GBP
|
— |
70,400,000
GBP
|
— | — | — | — | — | — | — | — | — |
70,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Current assets | — | — | — | — |
442,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
396,600,000
GBP
|
— |
364,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Assets | — | — | — | — |
1,282,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
1,252,100,000
GBP
|
— |
1,200,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||||||||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||||||||||||||||||||
| Issued capital | — | — | — | — |
75,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
75,600,000
GBP
|
— |
66,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Retained earnings | — | — | — | — |
333,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
300,800,000
GBP
|
— |
307,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other reserves | — | — | — | — |
132 .8
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
132,800,000
GBP
|
— |
132,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — | — | — | — |
612,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
604,700,000
GBP
|
— |
527,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Non-controlling interests | — | — | — | — |
16,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
13,300,000
GBP
|
— |
7,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity |
333,600,000
GBP
|
100,000
GBP
|
1,500,000
GBP
|
132,800,000
GBP
|
628,900,000
GBP
|
385,200,000
GBP
|
16,200,000
GBP
|
47,500,000
GBP
|
75,600,000
GBP
|
300,800,000
GBP
|
13,300,000
GBP
|
100,000
GBP
|
75,600,000
GBP
|
385,200,000
GBP
|
24,100,000
GBP
|
132,800,000
GBP
|
618,000,000
GBP
|
100,000
GBP
|
535,500,000
GBP
|
540,800,000
GBP
|
66,000,000
GBP
|
7,700,000
GBP
|
132,800,000
GBP
|
298,100,000
GBP
|
300,000
GBP
|
7,700,000
GBP
|
11,000,000
GBP
|
298,100,000
GBP
|
535,500,000
GBP
|
11,000,000
GBP
|
307,100,000
GBP
|
132,800,000
GBP
|
100,000
GBP
|
66,000,000
GBP
|
5,300,000
GBP
|
5,300,000
GBP
|
-
GBP
|
100,000
GBP
|
312,400,000
GBP
|
| Liabilities [abstract] | |||||||||||||||||||||||||||||||||||||||
| Non-current liabilities [abstract] | |||||||||||||||||||||||||||||||||||||||
| Non-current provisions [abstract] | |||||||||||||||||||||||||||||||||||||||
| Non-current provisions | — | — | — | — |
2,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
8,000,000
GBP
|
— |
6,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — | — | — | — |
45,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
45,500,000
GBP
|
— |
45,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other non-current financial liabilities | — | — | — | — |
5,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
1,200,000
GBP
|
— |
3,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Non-current liabilities | — | — | — | — |
437,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
427,700,000
GBP
|
— |
377,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Current liabilities [abstract] | |||||||||||||||||||||||||||||||||||||||
| Current provisions [abstract] | |||||||||||||||||||||||||||||||||||||||
| Current provisions | — | — | — | — |
1,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
5,500,000
GBP
|
— |
3,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Trade and other current payables | — | — | — | — |
180,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
155,400,000
GBP
|
— |
174,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Current liabilities | — | — | — | — |
215,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
206,400,000
GBP
|
— |
288,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Liabilities | — | — | — | — |
653,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
634,100,000
GBP
|
— |
665,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities | — | — | — | — |
1,282,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
1,252,100,000
GBP
|
— |
1,200,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |