Statement Of Financial Position [Abstract]
| Concept |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2023-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2022-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
As at 2021-04-30 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||||||||||||||
| Assets [abstract] | |||||||||||||||||||||||||||
| Property, plant and equipment | — |
3,529,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
3,128,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — |
224,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
199,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Investments accounted for using equity method | — |
17,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
17,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Current tax assets | — |
24,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
34,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — |
11,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
7,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — |
472,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
819,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Assets | — |
9,457,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
9,886,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||||||||
| Issued capital | — |
138,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
137,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Share premium | — |
2,251,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
2,248,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — |
4,084,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
4,232,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Non-controlling interests | — |
3,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
2,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity |
2,2 51
GBP
|
4,087,000,000
GBP
|
4,084,000,000
GBP
|
3,000,000
GBP
|
1,581,000,000
GBP
|
113,000,000
GBP
|
15,000,000
GBP
|
138,000,000
GBP
|
14,000,000
GBP
|
1,35 2
GBP
|
105,000,000
GBP
|
2, 248
GBP
|
4,232,000,000
GBP
|
2,000,000
GBP
|
137,000,000
GBP
|
9,000,000
GBP
|
4, 234
GBP
|
609,000,000
GBP
|
3,000,000
GBP
|
3,535,000,000
GBP
|
84,000,000
GBP
|
2,241,000,000
GBP
|
53,000,000
GBP
|
1,189,000,000
GBP
|
2,000,000
GBP
|
3,533,000,000
GBP
|
137,000,000
GBP
|
| Liabilities [abstract] | |||||||||||||||||||||||||||
| Current tax liabilities | — |
165,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
143,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — |
262,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
396,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Liabilities | — |
5,370,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
5,652,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |