Statement Of Cash Flows [Abstract]
| Concept |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
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] | |||||
| Cash flows from (used in) operations |
1 7 7. 7
GBP
|
— | — |
199. 5
GBP
|
— |
| Income taxes paid (refund), classified as operating activities |
2 2 . 4
GBP
|
— | — |
20 .6
GBP
|
— |
| Cash flows from (used in) operating activities |
155. 3
GBP
|
— | — |
178 . 9
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities |
5 . 3
GBP
|
— | — |
4 . 9
GBP
|
— |
| Proceeds from sales of property, plant and equipment, classified as investing activities |
3,900,000
GBP
|
— | — |
0 .7
GBP
|
— |
| Purchase of property, plant and equipment, classified as investing activities |
8 .0
GBP
|
— | — |
7. 6
GBP
|
— |
| Purchase of intangible assets, classified as investing activities |
2 . 8
GBP
|
— | — |
2 . 0
GBP
|
— |
| Dividends received, classified as investing activities |
0 .1
GBP
|
— | — |
0. 2
GBP
|
— |
| Interest received, classified as investing activities |
10. 3
GBP
|
— | — |
1. 3
GBP
|
— |
| Cash flows from (used in) investing activities |
38 .6
GBP
|
— | — |
5 . 4
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||
| Payments from changes in ownership interests in subsidiaries that do not result in loss of control |
–
GBP
|
— | — |
1,300,000
GBP
|
— |
| Proceeds from issuing shares |
1,900,000
GBP
|
— | — |
2,700,000
GBP
|
— |
| Repayments of borrowings, classified as financing activities |
0. 5
GBP
|
— | — |
0 . 6
GBP
|
— |
| Payments of lease liabilities, classified as financing activities |
10. 5
GBP
|
— | — |
1 1. 2
GBP
|
— |
| Interest paid, classified as financing activities |
2 .0
GBP
|
— | — |
2 . 2
GBP
|
— |
| Cash flows from (used in) financing activities |
9 0 .0
GBP
|
— | — |
6 3 . 2
GBP
|
— |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes |
26,700,000
GBP
|
— | — |
110. 3
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||
| Effect of exchange rate changes on cash and cash equivalents |
1 2. 2
GBP
|
— | — |
12. 5
GBP
|
— |
| Cash and cash equivalents | — |
398,900,000
GBP
|
384,400,000
GBP
|
— |
26 1.6
GBP
|