Statement Of Changes In Equity [Abstract]
| Concept |
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 |
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 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 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
As at 2020-03-31 |
As at 2020-03-31 |
As at 2020-03-31 |
As at 2020-03-31 |
As at 2020-03-31 |
As at 2020-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | ||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | ||||||||||||||||||||||||||||||
| Equity | — | — | — | — | — |
9,900,000
GBP
|
181,100,000
GBP
|
295,500,000
GBP
|
1,300,300,000
GBP
|
— |
1,7 99.6
GBP
|
32,600,000
GBP
|
9,600,000
GBP
|
1,219,400,000
GBP
|
33. 1
GBP
|
1,719,500,000
GBP
|
181,100,000
GBP
|
295,500,000
GBP
|
— | — | — | — | — | — |
32,200,000
GBP
|
1,998,000,000
GBP
|
9,600,000
GBP
|
295,400,000
GBP
|
1 80.7
GBP
|
1,499,300,000
GBP
|
| Changes in equity [abstract] | ||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | ||||||||||||||||||||||||||||||
| Profit (loss) |
–
GBP
|
–
GBP
|
123,900,000
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — |
123,900,000
GBP
|
— | — | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
235,700,000
GBP
|
–
GBP
|
–
GBP
|
235,700,000
GBP
|
— | — | — | — | — | — |
| Other comprehensive income |
–
GBP
|
–
GBP
|
1,800,000
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — |
1,800,000
GBP
|
— | — | — | — | — | — | — | — |
1,200,000
GBP
|
–
GBP
|
1,200,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — |
| Comprehensive income |
–
GBP
|
–
GBP
|
125,700,000
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — |
125,700,000
GBP
|
— | — | — | — | — | — | — | — |
1,200,000
GBP
|
–
GBP
|
236,900,000
GBP
|
–
GBP
|
–
GBP
|
235,700,000
GBP
|
— | — | — | — | — | — |
| Issue of equity | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
400,000
GBP
|
–
GBP
|
100,000
GBP
|
0. 4
GBP
|
0 .1
GBP
|
–
GBP
|
— | — | — | — | — | — |
| Dividends recognised as distributions to owners |
–
GBP
|
–
GBP
|
44,800,000
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — |
44,800,000
GBP
|
— | — | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
44,200,000
GBP
|
–
GBP
|
–
GBP
|
44,200,000
GBP
|
— | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity |
–
GBP
|
–
GBP
|
–
GBP
|
1,600,000
GBP
|
–
GBP
|
— | — | — | — |
1,600,000
GBP
|
— | — | — | — | — | — | — | — |
2,500,000
GBP
|
–
GBP
|
2,500,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — |