Statement Of Changes In Equity [Abstract]
| Concept |
As at 2023-04-01 |
As at 2023-04-01 |
As at 2023-04-01 |
As at 2023-04-01 |
As at 2023-04-01 |
As at 2023-04-01 |
2022-04-03 to 2023-04-01 |
2022-04-03 to 2023-04-01 |
2022-04-03 to 2023-04-01 |
As at 2023-04-01 |
2022-04-03 to 2023-04-01 |
2022-04-03 to 2023-04-01 |
2022-04-03 to 2023-04-01 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
2021-04-04 to 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
As at 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
As at 2021-04-03 |
As at 2021-04-03 |
As at 2021-04-03 |
As at 2021-04-03 |
As at 2021-04-03 |
As at 2021-04-03 |
As at 2021-04-01 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||
| Equity |
3,400,000
GBP
|
86,800,000
GBP
|
1,406,000,000
GBP
|
974,300,000
GBP
|
2,500,000
GBP
|
351,700,000
GBP
|
— | — | — |
9,300,000
GBP
|
— | — | — |
351,700,000
GBP
|
9,300,000
GBP
|
1,076,700,000
GBP
|
1,500,000
GBP
|
— |
86,300,000
GBP
|
1,506,900,000
GBP
|
— | — |
3,300,000
GBP
|
— | — | — |
9,300,000
GBP
|
755,100,000
GBP
|
351,700,000
GBP
|
1,183,600,000
GBP
|
85,500,000
GBP
|
600,000
GBP
|
3,700,000
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||
| Profit (loss) | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
91,600,000
GBP
|
91,600,000
GBP
|
–
GBP
|
— | — | — | — |
–
GBP
|
— | — |
–
GBP
|
77,500,000
GBP
|
— |
–
GBP
|
77,500,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Other comprehensive income | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
185,100,000
GBP
|
185,100,000
GBP
|
–
GBP
|
— | — | — | — |
–
GBP
|
— | — |
–
GBP
|
249,100,000
GBP
|
— |
–
GBP
|
249,100,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Comprehensive income | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
93,500,000
GBP
|
93,500,000
GBP
|
–
GBP
|
— | — | — | — |
–
GBP
|
— | — |
–
GBP
|
326,600,000
GBP
|
— |
–
GBP
|
326,600,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Issue of equity | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
1,000,000
GBP
|
— |
1,500,000
GBP
|
–
GBP
|
500,000
GBP
|
— | — | — | — |
–
GBP
|
— | — |
–
GBP
|
–
GBP
|
— |
900,000
GBP
|
1,700,000
GBP
|
800,000
GBP
|
— | — | — | — | — | — | — |
| Dividends recognised as distributions to owners | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
10,300,000
GBP
|
10,300,000
GBP
|
–
GBP
|
— | — | — | — |
–
GBP
|
— | — |
–
GBP
|
8,500,000
GBP
|
— |
–
GBP
|
8,500,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity | — | — | — | — | — | — |
–
GBP
|
–
GBP
|
–
GBP
|
— |
4,600,000
GBP
|
4,600,000
GBP
|
–
GBP
|
— | — | — | — |
–
GBP
|
— | — |
–
GBP
|
3,400,000
GBP
|
— |
–
GBP
|
3,400,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |