Statement Of Comprehensive Income [Abstract]
| Concept |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2024-04-01 to 2025-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
2023-04-01 to 2024-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||||||||||
| Profit (loss) |
28,700,000
GBP
|
28,100,000
GBP
|
28,100,000
GBP
|
28,700,000
GBP
|
56,800,000
GBP
|
1,100,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
57,900,000
GBP
|
9,500,000
GBP
|
21,000,000
GBP
|
12,500,000
GBP
|
12,500,000
GBP
|
21,000,000
GBP
|
8,500,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
1,000,000
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 | — | — |
3,500,000
GBP
|
–
GBP
|
3,500,000
GBP
|
— | — | — | — | — | — | — | — |
7,700,000
GBP
|
–
GBP
|
7 . 7
GBP
|
— | — | — | — |
| Components of other comprehensive income that will be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||||
| Cash flow hedges [abstract] | ||||||||||||||||||||
| Reclassification adjustments on cash flow hedges, before tax | — | — |
15,400,000
GBP
|
–
GBP
|
15,400,000
GBP
|
— | — | — | — | — | — | — | — |
18,300,000
GBP
|
–
GBP
|
18,300,000
GBP
|
— | — | — | — |
| Other comprehensive income, before tax, cash flow hedges | — | — |
19,700,000
GBP
|
–
GBP
|
19,700,000
GBP
|
— | — | — | — | — | — | — | — |
34,700,000
GBP
|
–
GBP
|
34,700,000
GBP
|
— | — | — | — |
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss [abstract] | ||||||||||||||||||||
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss | — | — |
900,000
GBP
|
–
GBP
|
900,000
GBP
|
— | — | — | — | — | — | — | — |
2,200,000
GBP
|
–
GBP
|
2,200,000
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 | — | — |
2,400,000
GBP
|
–
GBP
|
2,400,000
GBP
|
— | — | — | — | — | — | — | — |
4,100,000
GBP
|
–
GBP
|
4,100,000
GBP
|
— | — | — | — |
| Other comprehensive income | — | — |
700,000
GBP
|
–
GBP
|
700,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
700,000
GBP
|
17,800,000
GBP
|
— | — |
17,800,000
GBP
|
–
GBP
|
17,800,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
| Comprehensive income | — | — |
27,400,000
GBP
|
28,700,000
GBP
|
56,100,000
GBP
|
1,100,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
57,200,000
GBP
|
27,300,000
GBP
|
— | — |
5,300,000
GBP
|
21,000,000
GBP
|
26,300,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
1,000,000
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — |
57,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
27,300,000
GBP
|
— | — | — | — |
| Comprehensive income, attributable to non-controlling interests | — | — | — | — |
1,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
1,000,000
GBP
|
— | — | — | — |