Statement Of Cash Flows [Abstract]
| Concept |
2023-12-31 to 2024-12-28 |
As at 2024-12-28 |
2023-01-01 to 2023-12-30 |
As at 2023-12-30 |
As at 2022-12-31 |
|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||
| Cash flows from (used in) operating activities [abstract] | |||||
| Cash flows from (used in) operations |
352,600,000
GBP
|
— |
333,000,000
GBP
|
— | — |
| Income taxes paid (refund), classified as operating activities |
27 .7
GBP
|
— |
11,900,000
GBP
|
— | — |
| Cash flows from (used in) operating activities |
310,900,000
GBP
|
— |
3 10.8
GBP
|
— | — |
| Cash flows from (used in) investing activities [abstract] | |||||
| Proceeds from sales of property, plant and equipment, classified as investing activities |
16,100,000
GBP
|
— |
800,000
GBP
|
— | — |
| Purchase of property, plant and equipment, classified as investing activities |
230. 0
GBP
|
— |
189,500,000
GBP
|
— | — |
| Purchase of intangible assets, classified as investing activities |
10,900,000
GBP
|
— |
8,600,000
GBP
|
— | — |
| Interest received, classified as investing activities |
7. 7
GBP
|
— |
6,100,000
GBP
|
— | — |
| Cash flows from (used in) investing activities |
217 .1
GBP
|
— |
191,200,000
GBP
|
— | — |
| Cash flows from (used in) financing activities [abstract] | |||||
| Proceeds from issuing shares |
–
GBP
|
— |
2 .0
GBP
|
— | — |
| Payments to acquire or redeem entity's shares |
5,000,000
GBP
|
— |
5,000,000
GBP
|
— | — |
| Payments of lease liabilities, classified as financing activities |
56,700,000
GBP
|
— |
53,700,000
GBP
|
— | — |
| Dividends paid, classified as financing activities |
106,800,000
GBP
|
— |
60,800,000
GBP
|
— | — |
| Cash flows from (used in) financing activities |
163,800,000
GBP
|
— |
115,900,000
GBP
|
— | — |
| Increase (decrease) in cash and cash equivalents after effect of exchange rate changes |
70,000,000
GBP
|
— |
3,700,000
GBP
|
— | — |
| Cash and cash equivalents | — |
125,300,000
GBP
|
— |
195,300,000
GBP
|
191,600,000
GBP
|