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 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | ||||||||||||||||||
| Assets [abstract] | ||||||||||||||||||
| Non-current assets [abstract] | ||||||||||||||||||
| Property, plant and equipment | — | — | — | — | — |
5,361,600,000
GBP
|
4,476,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Goodwill | — | — | — | — | — |
179,500,000
GBP
|
163,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Intangible assets other than goodwill | — | — | — | — | — |
67,700,000
GBP
|
14,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — | — | — | — | — |
–
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-current assets | — | — | — | — | — |
5,663,400,000
GBP
|
4 ,743.0
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current assets [abstract] | ||||||||||||||||||
| Current inventories | — | — | — | — | — |
13,200,000
GBP
|
10,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other current receivables | — | — | — | — | — |
353,700,000
GBP
|
238,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — | — | — |
145,400,000
GBP
|
143,700,000
GBP
|
— | — | — | — | — | — | — | — | — |
351,200,000
GBP
|
— |
| Current assets | — | — | — | — | — |
567,700,000
GBP
|
442,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||
| Issued capital | — | — | — | — | — |
174,600,000
GBP
|
159,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Share premium | — | — | — | — | — |
398,200,000
GBP
|
237,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — | — | — | — | — |
1,161,200,000
GBP
|
1,124,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-controlling interests | — | — | — | — | — |
1,400,000
GBP
|
400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Equity |
431,300,000
GBP
|
1,400,000
GBP
|
398,200,000
GBP
|
174,600,000
GBP
|
157,100,000
GBP
|
1,162,600,000
GBP
|
1,125,200,000
GBP
|
237,600,000
GBP
|
159,500,000
GBP
|
570,600,000
GBP
|
157,100,000
GBP
|
400,000
GBP
|
154,700,000
GBP
|
161,700,000
GBP
|
235,500,000
GBP
|
722,600,000
GBP
|
1,274,600,000
GBP
|
100,000
GBP
|
| Liabilities [abstract] | ||||||||||||||||||
| Non-current liabilities [abstract] | ||||||||||||||||||
| Non-current provisions [abstract] | ||||||||||||||||||
| Non-current provisions | — | — | — | — | — |
400,000
GBP
|
–
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — | — | — | — | — |
548,300,000
GBP
|
507,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Non-current liabilities | — | — | — | — | — |
4,481,100,000
GBP
|
3,704,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current liabilities [abstract] | ||||||||||||||||||
| Current provisions [abstract] | ||||||||||||||||||
| Current provisions | — | — | — | — | — |
–
GBP
|
400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Trade and other current payables | — | — | — | — | — |
341,200,000
GBP
|
225,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |
| Current liabilities | — | — | — | — | — |
587,400,000
GBP
|
355,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — |