Statement Of Comprehensive Income [Abstract]
| Concept |
2024-03-31 to 2025-03-29 |
2024-03-31 to 2025-03-29 |
2024-03-31 to 2025-03-29 |
2024-03-31 to 2025-03-29 |
2024-03-31 to 2025-03-29 |
2024-03-31 to 2025-03-29 |
2023-04-02 to 2024-03-30 |
2023-04-02 to 2024-03-30 |
2023-04-02 to 2024-03-30 |
2023-04-02 to 2024-03-30 |
2023-04-02 to 2024-03-30 |
2023-04-02 to 2024-03-30 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||
| Profit (loss) |
124,900,000
GBP
|
–
GBP
|
–
GBP
|
124,900,000
GBP
|
–
GBP
|
–
GBP
|
112,500,000
GBP
|
–
GBP
|
–
GBP
|
112,500,000
GBP
|
–
GBP
|
–
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 |
13,600,000
GBP
|
–
GBP
|
–
GBP
|
13,600,000
GBP
|
–
GBP
|
–
GBP
|
237,700,000
GBP
|
–
GBP
|
–
GBP
|
237,700,000
GBP
|
–
GBP
|
–
GBP
|
| Other comprehensive income |
9,600,000
GBP
|
–
GBP
|
–
GBP
|
9,600,000
GBP
|
–
GBP
|
–
GBP
|
179,200,000
GBP
|
–
GBP
|
–
GBP
|
179,200,000
GBP
|
–
GBP
|
–
GBP
|
| Comprehensive income |
134,500,000
GBP
|
–
GBP
|
–
GBP
|
134,500,000
GBP
|
–
GBP
|
–
GBP
|
66,700,000
GBP
|
–
GBP
|
–
GBP
|
66,700,000
GBP
|
–
GBP
|
–
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||
| Comprehensive income, attributable to owners of parent |
134,500,000
GBP
|
— | — | — | — | — | — | — | — |
66,700,000
GBP
|
— | — |