Statement Of Financial Position [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 |
As at 2023-04-01 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2022-04-02 |
As at 2021-03-27 |
As at 2021-03-27 |
As at 2021-03-27 |
As at 2021-03-27 |
As at 2021-03-27 |
As at 2021-03-27 |
As at 2021-03-27 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||||||||
| Assets [abstract] | |||||||||||||||||||||
| Property, plant and equipment | — |
376,000,000
GBP
|
— | — | — | — | — | — | — | — |
322,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — |
950,000,000
GBP
|
— | — | — | — | — | — | — | — |
880,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Non-current assets or disposal groups classified as held for sale or as held for distribution to owners | — |
–
GBP
|
— | — | — | — | — | — | — | — |
13,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Current tax assets | — |
76,000,000
GBP
|
— | — | — | — | — | — | — | — |
86,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — |
197,000,000
GBP
|
— | — | — | — | — | — | — | — |
175,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — |
1,026,000,000
GBP
|
— | — | — | — | — | — | — | — |
1,222,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Assets | — |
3,686,000,000
GBP
|
— | — | — | — | — | — | — | — |
3,697,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||
| Issued capital | — |
–
GBP
|
— | — | — | — | — | — | — | — |
–
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Retained earnings | — |
1,026,000,000
GBP
|
— | — | — | — | — | — | — | — |
1,123,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Share premium | — |
230,000,000
GBP
|
— | — | — | — | — | — | — | — |
227,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — |
1,533,000,000
GBP
|
— | — | — | — | — | — | — | — |
1,613,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Non-controlling interests | — |
6,000,000
GBP
|
— | — | — | — | — | — | — | — |
4,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity |
–
GBP
|
1,539,000,000
GBP
|
1,026,000,000
GBP
|
230,000,000
GBP
|
277,000,000
GBP
|
1,533,000,000
GBP
|
6,000,000
GBP
|
1,12 3
GBP
|
227,000,000
GBP
|
–
GBP
|
1,617,000,000
GBP
|
263,000,000
GBP
|
1,613,000,000
GBP
|
4,000,000
GBP
|
242,000,000
GBP
|
1,092,000,000
GBP
|
1,560,000,000
GBP
|
–
GBP
|
223,000,000
GBP
|
1,557,000,000
GBP
|
3,000,000
GBP
|
| Liabilities [abstract] | |||||||||||||||||||||
| Current tax liabilities | — |
43,000,000
GBP
|
— | — | — | — | — | — | — | — |
39,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — |
1,000,000
GBP
|
— | — | — | — | — | — | — | — |
1,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Liabilities | — |
2,147,000,000
GBP
|
— | — | — | — | — | — | — | — |
2,080,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |