Statement Of Comprehensive Income [Abstract]
| Concept |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2022-03-27 to 2023-03-25 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
2021-03-28 to 2022-03-26 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||||||||
| Profit (loss) |
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
57 .2
GBP
|
1,300,000
GBP
|
55,900,000
GBP
|
2,200,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
21,500,000
GBP
|
–
GBP
|
23. 7
GBP
|
| Other comprehensive income [abstract] | ||||||||||||||||||
| Components of other comprehensive income that will not be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||
| Other comprehensive income, before tax, gains (losses) on remeasurements of defined benefit plans | — | — | — | — | — | — |
100,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
35,700,000
GBP
|
| Components of other comprehensive income that will be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||
| Exchange differences on translation [abstract] | ||||||||||||||||||
| Gains (losses) on exchange differences on translation of foreign operations, before tax | — | — | — | — | — | — |
5 .0
GBP
|
— | — | — | — | — | — | — | — | — | — |
1,500,000
GBP
|
| Reclassification adjustments on exchange differences on translation of foreign operations, before tax | — | — | — | — | — | — |
–
GBP
|
— | — | — | — | — | — | — | — | — | — |
100,000
GBP
|
| Cash flow hedges [abstract] | ||||||||||||||||||
| Gains (losses) on cash flow hedges, before tax | — | — | — | — | — | — |
1. 0
GBP
|
— | — | — | — | — | — | — | — | — | — |
600,000
GBP
|
| Reclassification adjustments on cash flow hedges, before tax | — | — | — | — | — | — |
1,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
0. 8
GBP
|
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss [abstract] | ||||||||||||||||||
| Income tax relating to remeasurements of defined benefit plans included in other comprehensive income | — | — | — | — | — | — |
24,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
8 . 8
GBP
|
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss [abstract] | ||||||||||||||||||
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss | — | — | — | — | — | — |
100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
100,000
GBP
|
| Other comprehensive income |
–
GBP
|
–
GBP
|
–
GBP
|
5 .0
GBP
|
0. 6
GBP
|
–
GBP
|
7 0.6
GBP
|
–
GBP
|
76 .2
GBP
|
100,000
GBP
|
–
GBP
|
–
GBP
|
1,500,000
GBP
|
0. 3
GBP
|
–
GBP
|
2 7. 1
GBP
|
–
GBP
|
2 6.0
GBP
|
| Comprehensive income |
–
GBP
|
–
GBP
|
–
GBP
|
5 .0
GBP
|
600,000
GBP
|
–
GBP
|
127 .8
GBP
|
1,300,000
GBP
|
132,100,000
GBP
|
2,300,000
GBP
|
–
GBP
|
–
GBP
|
1,500,000
GBP
|
0. 3
GBP
|
–
GBP
|
48. 6
GBP
|
–
GBP
|
49,700,000
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — |
126 .5
GBP
|
— | — | — | — | — | — | — | — | — | — |
47 .4
GBP
|
| Comprehensive income, attributable to non-controlling interests | — | — | — | — | — | — |
1,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
2,300,000
GBP
|