Statement Of Changes In Equity [Abstract]
| Concept |
As at 2023-07-31 |
As at 2023-07-31 |
2022-08-01 to 2023-07-31 |
As at 2023-07-31 |
As at 2023-07-31 |
2022-08-01 to 2023-07-31 |
2022-08-01 to 2023-07-31 |
2022-08-01 to 2023-07-31 |
2022-08-01 to 2023-07-31 |
As at 2023-07-31 |
2022-08-01 to 2023-07-31 |
As at 2023-07-31 |
As at 2022-07-31 |
As at 2022-07-31 |
As at 2022-07-31 |
As at 2022-07-31 |
As at 2022-07-31 |
2021-08-01 to 2022-07-31 |
2021-08-01 to 2022-07-31 |
2021-08-01 to 2022-07-31 |
2021-08-01 to 2022-07-31 |
2021-08-01 to 2022-07-31 |
2021-08-01 to 2022-07-31 |
As at 2022-07-31 |
As at 2021-07-31 |
As at 2021-07-31 |
As at 2021-07-31 |
As at 2021-07-31 |
As at 2021-07-31 |
As at 2021-07-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | ||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | ||||||||||||||||||||||||||||||
| Equity |
182,000,000
GBP
|
15,000,000
GBP
|
— |
20,400,000
GBP
|
3,242,700,000
GBP
|
— | — | — | — |
3,461,600,000
GBP
|
— |
1,500,000
GBP
|
182,000,000
GBP
|
15,400,000
GBP
|
20,000,000
GBP
|
3,148,900,000
GBP
|
3,367,800,000
GBP
|
— | — | — | — | — | — |
1,500,000
GBP
|
179,800,000
GBP
|
3,287,800,000
GBP
|
1,500,000
GBP
|
15,400,000
GBP
|
3,071,100,000
GBP
|
20,000,000
GBP
|
| Changes in equity [abstract] | ||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | ||||||||||||||||||||||||||||||
| Profit (loss) | — | — |
–
GBP
|
— | — |
–
GBP
|
365,000,000
GBP
|
–
GBP
|
365,000,000
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
242,600,000
GBP
|
–
GBP
|
–
GBP
|
242,600,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Other comprehensive income | — | — |
–
GBP
|
— | — |
–
GBP
|
3,500,000
GBP
|
–
GBP
|
3,500,000
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
3,000,000
GBP
|
–
GBP
|
–
GBP
|
3,000,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Comprehensive income | — | — |
–
GBP
|
— | — |
–
GBP
|
361,500,000
GBP
|
–
GBP
|
361,500,000
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
239,600,000
GBP
|
–
GBP
|
–
GBP
|
239,600,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Issue of equity | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
2,200,000
GBP
|
2,200,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Dividends recognised as distributions to owners | — | — |
–
GBP
|
— | — |
–
GBP
|
171,700,000
GBP
|
–
GBP
|
171,700,000
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
157,200,000
GBP
|
–
GBP
|
–
GBP
|
157,200,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity | — | — |
–
GBP
|
— | — |
–
GBP
|
4,500,000
GBP
|
–
GBP
|
4,500,000
GBP
|
— |
–
GBP
|
— | — | — | — | — | — |
–
GBP
|
2,800,000
GBP
|
–
GBP
|
–
GBP
|
2,800,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — |