Statement Of Financial Position [Abstract]
| Concept |
As at 2025-03-31 |
As at 2025-03-31 |
As at 2025-03-31 |
As at 2025-03-31 |
As at 2025-03-31 |
As at 2025-03-31 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | ||||||||||||||||||
| Assets [abstract] | ||||||||||||||||||
| Non-current assets [abstract] | ||||||||||||||||||
| Property, plant and equipment | — | — | — | — |
85,600,000
GBP
|
— | — | — | — | — |
80. 5
GBP
|
— | — | — | — | — | — | — |
| Right-of-use assets | — | — | — | — |
29,900,000
GBP
|
— | — | — | — | — |
32,400,000
GBP
|
— | — | — | — | — | — | — |
| Trade and other non-current receivables | — | — | — | — |
1 .0
GBP
|
— | — | — | — | — |
1 .3
GBP
|
— | — | — | — | — | — | — |
| Deferred tax assets | — | — | — | — |
11 . 1
GBP
|
— | — | — | — | — |
13 .7
GBP
|
— | — | — | — | — | — | — |
| Non-current assets | — | — | — | — |
2 74 . 1
GBP
|
— | — | — | — | — |
28 2.4
GBP
|
— | — | — | — | — | — | — |
| Current assets [abstract] | ||||||||||||||||||
| Current inventories | — | — | — | — |
9 9.1
GBP
|
— | — | — | — | — |
108 . 1
GBP
|
— | — | — | — | — | — | — |
| Trade and other current receivables | — | — | — | — |
126. 2
GBP
|
— | — | — | — | — |
114 . 7
GBP
|
— | — | — | — | — | — | — |
| Cash and cash equivalents | — | — | — | — |
94. 1
GBP
|
— | — | — | — | — |
97. 8
GBP
|
— | — | — | — | — | — | — |
| Current assets | — | — | — | — |
330. 7
GBP
|
— | — | — | — | — |
323 .9
GBP
|
— | — | — | — | — | — | — |
| Assets | — | — | — | — |
604,800,000
GBP
|
— | — | — | — | — |
606. 3
GBP
|
— | — | — | — | — | — | — |
| Equity and liabilities [abstract] | ||||||||||||||||||
| Equity [abstract] | ||||||||||||||||||
| Issued capital | — | — | — | — |
2 .9
GBP
|
— | — | — | — | — |
2,900,000
GBP
|
— | — | — | — | — | — | — |
| Retained earnings | — | — | — | — |
305 .0
GBP
|
— | — | — | — | — |
292,600,000
GBP
|
— | — | — | — | — | — | — |
| Share premium | — | — | — | — |
62 .6
GBP
|
— | — | — | — | — |
62. 6
GBP
|
— | — | — | — | — | — | — |
| Other reserves | — | — | — | — |
0. 2
GBP
|
— | — | — | — | — |
0. 2
GBP
|
— | — | — | — | — | — | — |
| Equity |
2,900,000
GBP
|
0. 2
GBP
|
5,400,000
GBP
|
30 5.0
GBP
|
376 . 1
GBP
|
62 .6
GBP
|
0. 2
GBP
|
2 92 .6
GBP
|
62 .6
GBP
|
2,900,000
GBP
|
365 .7
GBP
|
7. 4
GBP
|
3 4 4.0
GBP
|
62,600,000
GBP
|
12,900,000
GBP
|
2,900,000
GBP
|
265 .4
GBP
|
0. 2
GBP
|
| Liabilities [abstract] | ||||||||||||||||||
| Non-current liabilities [abstract] | ||||||||||||||||||
| Non-current provisions [abstract] | ||||||||||||||||||
| Non-current provisions | — | — | — | — |
1,300,000
GBP
|
— | — | — | — | — |
–
GBP
|
— | — | — | — | — | — | — |
| Deferred tax liabilities | — | — | — | — |
16. 7
GBP
|
— | — | — | — | — |
12,900,000
GBP
|
— | — | — | — | — | — | — |
| Non-current liabilities | — | — | — | — |
46,100,000
GBP
|
— | — | — | — | — |
42,400,000
GBP
|
— | — | — | — | — | — | — |
| Current liabilities [abstract] | ||||||||||||||||||
| Current provisions [abstract] | ||||||||||||||||||
| Current provisions | — | — | — | — |
4,600,000
GBP
|
— | — | — | — | — |
6,400,000
GBP
|
— | — | — | — | — | — | — |
| Trade and other current payables | — | — | — | — |
1 5 7. 7
GBP
|
— | — | — | — | — |
166 . 2
GBP
|
— | — | — | — | — | — | — |
| Current liabilities | — | — | — | — |
182 .6
GBP
|
— | — | — | — | — |
198. 2
GBP
|
— | — | — | — | — | — | — |
| Liabilities | — | — | — | — |
228,700,000
GBP
|
— | — | — | — | — |
24 0 . 6
GBP
|
— | — | — | — | — | — | — |
| Equity and liabilities | — | — | — | — |
604,800,000
GBP
|
— | — | — | — | — |
606. 3
GBP
|
— | — | — | — | — | — | — |