Statement Of Financial Position [Abstract]
| Concept |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2024-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2023-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
As at 2022-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | ||||||||||||||||||||||||||||||
| Assets [abstract] | ||||||||||||||||||||||||||||||
| Property, plant and equipment | — | — | — | — | — | — | — | — |
517,100,000
GBP
|
— | — | — | — |
478,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — | — | — | — | — | — | — | — |
175,600,000
GBP
|
— | — | — | — |
159,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Goodwill | — | — | — | — | — | — | — | — |
780,100,000
GBP
|
— | — | — | — |
781,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Intangible assets other than goodwill | — | — | — | — | — | — | — | — |
148,800,000
GBP
|
— | — | — | — |
140,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Investments accounted for using equity method | — | — | — | — | — | — | — | — |
59,700,000
GBP
|
— | — | — | — |
57,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Current tax assets | — | — | — | — | — | — | — | — |
10,600,000
GBP
|
— | — | — | — |
7,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — | — | — | — | — | — | — | — |
132,300,000
GBP
|
— | — | — | — |
112,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — | — | — | — | — | — |
570,600,000
GBP
|
— | — | — | — |
451,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Assets | — | — | — | — | — | — | — | — |
3,580,100,000
GBP
|
— | — | — | — |
3,309,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||||||||||||||
| Issued capital | — | — | — | — | — | — | — | — |
303,400,000
GBP
|
— | — | — | — |
303,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Retained earnings | — | — | — | — | — | — | — | — |
1,523,900,000
GBP
|
— | — | — | — |
1,568,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Share premium | — | — | — | — | — | — | — | — |
873,000,000
GBP
|
— | — | — | — |
873,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other reserves | — | — | — | — | — | — | — | — |
736,400,000
GBP
|
— | — | — | — |
746,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — | — | — | — | — | — | — | — |
388,900,000
GBP
|
— | — | — | — |
353,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Non-controlling interests | — | — | — | — | — | — | — | — |
17,200,000
GBP
|
— | — | — | — |
17,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity |
388,900,000
GBP
|
5,300,000
GBP
|
768,800,000
GBP
|
1,523. 9
GBP
|
17,200,000
GBP
|
873,000,000
GBP
|
303,400,000
GBP
|
30,600,000
GBP
|
406,100,000
GBP
|
68,300,000
GBP
|
353,900,000
GBP
|
3,000,000
GBP
|
768,800,000
GBP
|
370,900,000
GBP
|
873,000,000
GBP
|
303,400,000
GBP
|
30,600,000
GBP
|
17,000,000
GBP
|
1,568,800,000
GBP
|
56,100,000
GBP
|
30,600,000
GBP
|
682,000,000
GBP
|
768,800,000
GBP
|
4,000,000
GBP
|
303,400,000
GBP
|
1,241,400,000
GBP
|
56,400,000
GBP
|
873,000,000
GBP
|
701,500,000
GBP
|
19,500,000
GBP
|
| Liabilities [abstract] | ||||||||||||||||||||||||||||||
| Current tax liabilities | — | — | — | — | — | — | — | — |
16,600,000
GBP
|
— | — | — | — |
15,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — | — | — | — | — | — | — | — |
6,400,000
GBP
|
— | — | — | — |
7,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Liabilities | — | — | — | — | — | — | — | — |
3,174,000,000
GBP
|
— | — | — | — |
2,939,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities | — | — | — | — | — | — | — | — |
3,580,100,000
GBP
|
— | — | — | — |
3,309,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |