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 |
2021-04-01 to 2022-03-31 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | ||||||||||||
| Statement of changes in equity [line items] | ||||||||||||
| Decrease (increase) through tax on share-based payment transactions, equity | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
1,000,000
GBP
|
1,000,000
GBP
|
| Purchase of treasury shares |
–
GBP
|
–
GBP
|
200,000,000
GBP
|
3,000,000
GBP
|
3,000,000
GBP
|
2 00
GBP
|
— | — | — | — | — | — |
| Share issue related cost |
–
GBP
|
5,000,000
GBP
|
1 3
GBP
|
–
GBP
|
–
GBP
|
8,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
3,000,000
GBP
|
10,000,000
GBP
|
7,000,000
GBP
|