Statement Of Changes In Equity [Abstract]
| Concept |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
2022-04-01 to 2023-03-31 |
As at 2023-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
As at 2022-03-31 |
2021-04-01 to 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
2021-04-01 to 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||
| Equity | — | — |
1,344,200,000
GBP
|
1,344,900,000
GBP
|
2,200,000
GBP
|
— | — |
700,000
GBP
|
954,300,000
GBP
|
283,300,000
GBP
|
— | — | — |
108,800,000
GBP
|
— | — | — | — | — |
60,200,000
GBP
|
— |
3,000,000
GBP
|
1,108,500,000
GBP
|
772,800,000
GBP
|
— |
1,108,500,000
GBP
|
278,500,000
GBP
|
–
GBP
|
1,500,000
GBP
|
587,800,000
GBP
|
37,600,000
GBP
|
899,400,000
GBP
|
275,500,000
GBP
|
–
GBP
|
899,400,000
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||
| Profit (loss) |
284,800,000
GBP
|
284,800,000
GBP
|
— | — | — |
–
GBP
|
284,800,000
GBP
|
— | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
230,000,000
GBP
|
–
GBP
|
–
GBP
|
230,000,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — |
230,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Other comprehensive income |
25,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
43,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Comprehensive income |
310,100,000
GBP
|
310,100,000
GBP
|
— | — | — |
–
GBP
|
258,500,000
GBP
|
— | — | — |
–
GBP
|
51,600,000
GBP
|
–
GBP
|
— |
273,900,000
GBP
|
–
GBP
|
–
GBP
|
250,900,000
GBP
|
23,000,000
GBP
|
— |
–
GBP
|
— | — | — |
273,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Dividends recognised as distributions to owners |
88,600,000
GBP
|
88,600,000
GBP
|
— | — | — |
–
GBP
|
88,600,000
GBP
|
— | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
76,200,000
GBP
|
–
GBP
|
–
GBP
|
76,200,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — |
76,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through changes in ownership interests in subsidiaries that do not result in loss of control, equity |
–
GBP
|
700,000
GBP
|
— | — | — |
700,000
GBP
|
700,000
GBP
|
— | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity |
14,200,000
GBP
|
14,200,000
GBP
|
— | — | — |
–
GBP
|
14,200,000
GBP
|
— | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
9,900,000
GBP
|
–
GBP
|
–
GBP
|
9,900,000
GBP
|
–
GBP
|
— |
–
GBP
|
— | — | — |
9,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Amount removed from reserve of cash flow hedges and included in initial cost or other carrying amount of non-financial asset (liability) or firm commitment for which fair value hedge accounting is applied |
3,700,000
GBP
|
3,700,000
GBP
|
— | — | — |
–
GBP
|
–
GBP
|
— | — | — |
–
GBP
|
3,700,000
GBP
|
–
GBP
|
— |
500,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
500,000
GBP
|
— |
–
GBP
|
— | — | — |
500,000
GBP
|
— | — | — | — | — | — | — | — | — | — |