Statement Of Cash Flows [Abstract]
| Concept |
2022-01-02 to 2022-12-31 |
As at 2022-12-31 |
2022-01-02 to 2022-12-31 |
2022-01-02 to 2022-12-31 |
2022-01-02 to 2022-12-31 |
2022-01-02 to 2022-12-31 |
As at 2022-01-02 |
As at 2022-01-01 |
2021-01-03 to 2022-01-01 |
2021-01-03 to 2022-01-01 |
2021-01-03 to 2022-01-01 |
2021-01-03 to 2022-01-01 |
2021-01-03 to 2022-01-01 |
As at 2021-01-03 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | ||||||||||||||
| Cash flows from (used in) operating activities [abstract] | ||||||||||||||
| Profit (loss) |
–
GBP
|
— |
120,300,000
GBP
|
–
GBP
|
–
GBP
|
120,300,000
GBP
|
— | — |
1 1 7. 5
GBP
|
1 1 7. 5
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— |
| Adjustments to reconcile profit (loss) [abstract] | ||||||||||||||
| Adjustments for income tax expense | — | — |
28,000,000
GBP
|
— | — | — | — | — |
2 8 .1
GBP
|
— | — | — | — | — |
| Adjustments for finance costs | — | — |
6 .1
GBP
|
— | — | — | — | — |
7. 6
GBP
|
— | — | — | — | — |
| Adjustments for decrease (increase) in inventories | — | — |
1 2 .7
GBP
|
— | — | — | — | — |
5 . 4
GBP
|
— | — | — | — | — |
| Adjustments for provisions | — | — |
0 .7
GBP
|
— | — | — | — | — |
0 .4
GBP
|
— | — | — | — | — |
| Adjustments for share-based payments | — | — |
3,600,000
GBP
|
— | — | — | — | — |
2. 2
GBP
|
— | — | — | — | — |
| Cash flows from (used in) operations | — | — |
27 2 .3
GBP
|
— | — | — | — | — |
3 1 2 .1
GBP
|
— | — | — | — | — |
| Income taxes paid (refund), classified as operating activities | — | — |
1 3. 3
GBP
|
— | — | — | — | — |
1 9. 2
GBP
|
— | — | — | — | — |
| Cash flows from (used in) operating activities | — | — |
251 .5
GBP
|
— | — | — | — | — |
28 5.5
GBP
|
— | — | — | — | — |
| Cash flows from (used in) investing activities [abstract] | ||||||||||||||
| Proceeds from sales of property, plant and equipment, classified as investing activities | — | — |
900,000
GBP
|
— | — | — | — | — |
300,000
GBP
|
— | — | — | — | — |
| Purchase of property, plant and equipment, classified as investing activities | — | — |
1 0 0 . 0
GBP
|
— | — | — | — | — |
5 0.5
GBP
|
— | — | — | — | — |
| Purchase of intangible assets, classified as investing activities | — | — |
3. 3
GBP
|
— | — | — | — | — |
3 .8
GBP
|
— | — | — | — | — |
| Interest received, classified as investing activities | — | — |
1,400,000
GBP
|
— | — | — | — | — |
–
GBP
|
— | — | — | — | — |
| Cash flows from (used in) investing activities | — | — |
9 9 . 4
GBP
|
— | — | — | — | — |
5 4. 0
GBP
|
— | — | — | — | — |
| Cash flows from (used in) financing activities [abstract] | ||||||||||||||
| Proceeds from issuing shares | — | — |
3 .1
GBP
|
— | — | — | — | — |
4,300,000
GBP
|
— | — | — | — | — |
| Payments to acquire or redeem entity's shares | — | — |
1 1 . 0
GBP
|
— | — | — | — | — |
1 0 . 0
GBP
|
— | — | — | — | — |
| Payments of lease liabilities, classified as financing activities | — | — |
5 2 .7
GBP
|
— | — | — | — | — |
4 9 .0
GBP
|
— | — | — | — | — |
| Dividends paid, classified as financing activities | — | — |
9 8 .5
GBP
|
— | — | — | — | — |
15,300,000
GBP
|
— | — | — | — | — |
| Cash flows from (used in) financing activities | — | — |
1 5 9 .1
GBP
|
— | — | — | — | — |
6 9.7
GBP
|
— | — | — | — | — |
| Increase (decrease) in cash and cash equivalents after effect of exchange rate changes | — | — |
7. 0
GBP
|
— | — | — | — | — |
1 61.8
GBP
|
— | — | — | — | — |
| Cash and cash equivalents | — |
1 9 1.6
GBP
|
— | — | — | — |
1 98 .6
GBP
|
19 8.6
GBP
|
— | — | — | — | — |
3 6.8
GBP
|