Statement Of Financial Position [Abstract]
| Concept |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2022-01-29 |
As at 2021-01-31 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2021-01-30 |
As at 2020-01-26 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
As at 2020-01-25 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | ||||||||||||||||||||||||||||||||
| Assets [abstract] | ||||||||||||||||||||||||||||||||
| Property, plant and equipment | — | — | — | — | — | — |
601,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
474,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — | — | — | — | — | — |
639,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
720,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Investments in subsidiaries, joint ventures and associates reported in separate financial statements | — | — | — | — | — | — |
46,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
5,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — | — | — | — | — | — |
34,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
70,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — | — | — | — |
199,900,000
GBP
|
— | — | — |
514,800,000
GBP
|
— | — | — | — | — | — |
514,800,000
GBP
|
— | — | — |
52,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Assets | — | — | — | — | — | — |
3,981,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
3,758,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||||||||||||||||
| Equity |
13,300,000
GBP
|
16,600,000
GBP
|
900,000
GBP
|
27,900,000
GBP
|
331,700,000
GBP
|
2,731,000,000
GBP
|
1,010,000,000
GBP
|
700,000
GBP
|
1,443,800,000
GBP
|
4,900,000
GBP
|
— |
16,600,000
GBP
|
19,700,000
GBP
|
271,200,000
GBP
|
100,000
GBP
|
1,443,800,000
GBP
|
2,367,200,000
GBP
|
660,900,000
GBP
|
13,300,000
GBP
|
2,500,000
GBP
|
900,000
GBP
|
— |
441,500,000
GBP
|
900,000
GBP
|
2,163,600,000
GBP
|
1,443,800,000
GBP
|
13,300,000
GBP
|
16,600,000
GBP
|
284,900,000
GBP
|
24,700,000
GBP
|
500,000
GBP
|
–
GBP
|
| Liabilities [abstract] | ||||||||||||||||||||||||||||||||
| Current tax liabilities | — | — | — | — | — | — |
13,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
14,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Liabilities | — | — | — | — | — | — |
2,971,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
3,097,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — |