Statement Of Cash Flows [Abstract]
| Concept |
2023-01-01 to 2023-12-31 |
2023-01-01 to 2023-12-31 |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
As at 2022-12-31 |
2022-01-01 to 2022-12-31 |
As at 2021-12-31 |
|---|---|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||||||
| Cash flows from (used in) operating activities [abstract] | |||||||||
| Profit (loss) |
114,700,000
GBP
|
9 .1
GBP
|
105,600,000
GBP
|
— |
118 .8
GBP
|
6 . 2
GBP
|
— |
112,600,000
GBP
|
— |
| Adjustments to reconcile profit (loss) [abstract] | |||||||||
| Adjustments for income tax expense | — | — |
28. 8
GBP
|
— | — | — | — |
23. 2
GBP
|
— |
| Adjustments for finance costs | — | — |
13. 9
GBP
|
— | — | — | — |
12,400,000
GBP
|
— |
| Adjustments for decrease (increase) in inventories | — | — |
24 .6
GBP
|
— | — | — | — |
3 1 .7
GBP
|
— |
| Adjustments for provisions | — | — |
8,300,000
GBP
|
— | — | — | — |
7. 7
GBP
|
— |
| Adjustments for share-based payments | — | — |
3,000,000
GBP
|
— | — | — | — |
1. 2
GBP
|
— |
| Cash flows from (used in) operations | — | — |
230,900,000
GBP
|
— | — | — | — |
2 02. 8
GBP
|
— |
| Interest paid, classified as operating activities | — | — |
6 . 8
GBP
|
— | — | — | — |
6 . 7
GBP
|
— |
| Interest received, classified as operating activities | — | — |
2,600,000
GBP
|
— | — | — | — |
0. 2
GBP
|
— |
| Income taxes paid (refund), classified as operating activities | — | — |
32 . 5
GBP
|
— | — | — | — |
25 . 8
GBP
|
— |
| Cash flows from (used in) operating activities | — | — |
191. 9
GBP
|
— | — | — | — |
168 .0
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities | — | — |
1 8 . 8
GBP
|
— | — | — | — |
1 2. 6
GBP
|
— |
| Proceeds from sales of property, plant and equipment, classified as investing activities | — | — |
3,400,000
GBP
|
— | — | — | — |
4,800,000
GBP
|
— |
| Purchase of property, plant and equipment, classified as investing activities | — | — |
1 06 . 8
GBP
|
— | — | — | — |
1 0 6 . 8
GBP
|
— |
| Cash flows from (used in) investing activities | — | — |
120. 4
GBP
|
— | — | — | — |
1 1 2 . 9
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||||||
| Proceeds from issuing shares | — | — |
700,000
GBP
|
— | — | — | — |
2,000,000
GBP
|
— |
| Repayments of borrowings, classified as financing activities | — | — |
0 . 9
GBP
|
— | — | — | — |
–
GBP
|
— |
| Payments of lease liabilities, classified as financing activities | — | — |
8 .1
GBP
|
— | — | — | — |
8 . 8
GBP
|
— |
| Dividends paid, classified as financing activities | — | — |
37. 6
GBP
|
— | — | — | — |
30,500,000
GBP
|
— |
| Cash flows from (used in) financing activities | — | — |
4 6. 6
GBP
|
— | — | — | — |
3 8 . 0
GBP
|
— |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes | — | — |
24. 9
GBP
|
— | — | — | — |
1 7.1
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||||||
| Effect of exchange rate changes on cash and cash equivalents | — | — |
300,000
GBP
|
— | — | — | — |
700,000
GBP
|
— |
| Cash and cash equivalents | — | — | — |
126 .9
GBP
|
— | — |
101 .7
GBP
|
— |
83 .9
GBP
|