Statement Of Cash Flows [Abstract]
| Concept |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
As at 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2024-01-01 to 2024-12-31 |
2023-01-01 to 2023-12-31 |
2023-01-01 to 2023-12-31 |
As at 2023-12-31 |
2023-01-01 to 2023-12-31 |
2023-01-01 to 2023-12-31 |
2023-01-01 to 2023-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | ||||||||||||||
| Cash flows from (used in) operating activities [abstract] | ||||||||||||||
| Profit (loss) |
4,300,000
GBP
|
–
GBP
|
69,100,000
GBP
|
–
GBP
|
— |
–
GBP
|
64,800,000
GBP
|
64,800,000
GBP
|
–
GBP
|
70,700,000
GBP
|
— |
–
GBP
|
70,700,000
GBP
|
–
GBP
|
| Cash flows from (used in) operations | — | — |
12,300,000
GBP
|
— | — | — | — | — | — |
99,700,000
GBP
|
— | — | — | — |
| Income taxes paid (refund), classified as operating activities | — | — |
1,500,000
GBP
|
— | — | — | — | — | — |
4,700,000
GBP
|
— | — | — | — |
| Cash flows from (used in) operating activities | — | — |
10,800,000
GBP
|
— | — | — | — | — | — |
95,000,000
GBP
|
— | — | — | — |
| Cash flows from (used in) investing activities [abstract] | ||||||||||||||
| Cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities | — | — |
162,800,000
GBP
|
— | — | — | — | — | — |
–
GBP
|
— | — | — | — |
| Cash payments for futures contracts, forward contracts, option contracts and swap contracts, classified as investing activities | — | — |
–
GBP
|
— | — | — | — | — | — |
3,800,000
GBP
|
— | — | — | — |
| Cash flows from (used in) investing activities | — | — |
928,900,000
GBP
|
— | — | — | — | — | — |
320,000,000
GBP
|
— | — | — | — |
| Cash flows from (used in) financing activities [abstract] | ||||||||||||||
| Payments to acquire or redeem entity's shares | — | — |
9,800,000
GBP
|
— | — | — | — | — | — |
60,200,000
GBP
|
— | — | — | — |
| Payments of lease liabilities, classified as financing activities | — | — |
15,400,000
GBP
|
— | — | — | — | — | — |
6,600,000
GBP
|
— | — | — | — |
| Interest paid, classified as financing activities | — | — |
14,200,000
GBP
|
— | — | — | — | — | — |
7,200,000
GBP
|
— | — | — | — |
| Cash flows from (used in) financing activities | — | — |
776,100,000
GBP
|
— | — | — | — | — | — |
325,600,000
GBP
|
— | — | — | — |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes | — | — |
142,000,000
GBP
|
— | — | — | — | — | — |
100,600,000
GBP
|
— | — | — | — |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | ||||||||||||||
| Effect of exchange rate changes on cash and cash equivalents | — | — |
13,000,000
GBP
|
— | — | — | — | — | — |
6,400,000
GBP
|
— | — | — | — |
| Cash and cash equivalents | — | — | — | — |
90,800,000
GBP
|
— | — | — | — | — |
238,800,000
GBP
|
— | — | — |