Statement Of Comprehensive Income [Abstract]
| Concept |
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 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
2021-04-01 to 2022-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | |||||||||||||
| Profit (loss) |
–
GBP
|
–
GBP
|
50. 7
GBP
|
–
GBP
|
–
GBP
|
5 0.7
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
58,600,000
GBP
|
–
GBP
|
58,600,000
GBP
|
58,600,000
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 |
–
GBP
|
–
GBP
|
19. 4
GBP
|
–
GBP
|
–
GBP
|
19. 4
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
3 8. 6
GBP
|
–
GBP
|
3 8 .6
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 |
–
GBP
|
–
GBP
|
4,800,000
GBP
|
–
GBP
|
–
GBP
|
4,800,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
9,700,000
GBP
|
–
GBP
|
9. 7
GBP
|
— |
| Other comprehensive income | — | — |
20. 2
GBP
|
— | — | — | — | — | — | — | — |
23,600,000
GBP
|
— |
| Comprehensive income attributable to [abstract] | |||||||||||||
| Comprehensive income, attributable to owners of parent |
–
GBP
|
5. 5
GBP
|
3 0.6
GBP
|
–
GBP
|
–
GBP
|
36,100,000
GBP
|
–
GBP
|
5,300,000
GBP
|
–
GBP
|
29. 7
GBP
|
–
GBP
|
3 5.0
GBP
|
— |