Statement Of Financial Position [Abstract]
| Concept |
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 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
As at 2021-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of financial position [abstract] | |||||||||||||||||||||
| Assets [abstract] | |||||||||||||||||||||
| Non-current assets [abstract] | |||||||||||||||||||||
| Property, plant and equipment | — |
186,300,000
GBP
|
— | — | — | — | — | — | — | — |
177,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Right-of-use assets | — |
46,900,000
GBP
|
— | — | — | — | — | — | — | — |
45,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Deferred tax assets | — |
6,900,000
GBP
|
— | — | — | — | — | — | — | — |
4,900,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Non-current assets | — |
953,700,000
GBP
|
— | — | — | — | — | — | — | — |
706,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Current assets [abstract] | |||||||||||||||||||||
| Current inventories | — |
616,300,000
GBP
|
— | — | — | — | — | — | — | — |
529,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Trade and other current receivables | — |
692,000,000
GBP
|
— | — | — | — | — | — | — | — |
594,300,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Cash and cash equivalents | — |
120,500,000
GBP
|
— | — | — | — | — | — | — | — |
158,400,000
GBP
|
— | — | — | — | — | — |
86,400,000
GBP
|
— | — | — |
| Current assets | — |
1,590,300,000
GBP
|
— | — | — | — | — | — | — | — |
1,395,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Assets | — |
2,544,000,000
GBP
|
— | — | — | — | — | — | — | — |
2,101,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity and liabilities [abstract] | |||||||||||||||||||||
| Equity [abstract] | |||||||||||||||||||||
| Retained earnings | — |
954,300,000
GBP
|
— | — | — | — | — | — | — | — |
772,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Treasury shares | — |
2,200,000
GBP
|
— | — | — | — | — | — | — | — |
3,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Other reserves | — |
108,800,000
GBP
|
— | — | — | — | — | — | — | — |
60,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity attributable to owners of parent | — |
1,344,200,000
GBP
|
— | — | — | — | — | — | — | — |
1,108,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Non-controlling interests | — |
700,000
GBP
|
— | — | — | — | — | — | — | — |
–
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Equity |
1,344,200,000
GBP
|
1,344,900,000
GBP
|
2,200,000
GBP
|
700,000
GBP
|
954,300,000
GBP
|
283,300,000
GBP
|
108,800,000
GBP
|
3,000,000
GBP
|
1,108,500,000
GBP
|
772,800,000
GBP
|
1,108,500,000
GBP
|
–
GBP
|
278,500,000
GBP
|
60,200,000
GBP
|
1,500,000
GBP
|
587,800,000
GBP
|
37,600,000
GBP
|
899,400,000
GBP
|
275,500,000
GBP
|
–
GBP
|
899,400,000
GBP
|
| Liabilities [abstract] | |||||||||||||||||||||
| Non-current liabilities [abstract] | |||||||||||||||||||||
| Non-current provisions [abstract] | |||||||||||||||||||||
| Non-current provisions | — |
4,700,000
GBP
|
— | — | — | — | — | — | — | — |
2,800,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Deferred tax liabilities | — |
90,100,000
GBP
|
— | — | — | — | — | — | — | — |
60,400,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Non-current liabilities | — |
360,200,000
GBP
|
— | — | — | — | — | — | — | — |
266,500,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Current liabilities [abstract] | |||||||||||||||||||||
| Current provisions [abstract] | |||||||||||||||||||||
| Current provisions | — |
1,800,000
GBP
|
— | — | — | — | — | — | — | — |
2,600,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Trade and other current payables | — |
658,900,000
GBP
|
— | — | — | — | — | — | — | — |
584,100,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Current liabilities | — |
838,900,000
GBP
|
— | — | — | — | — | — | — | — |
726,200,000
GBP
|
— | — | — | — | — | — | — | — | — | — |
| Liabilities | — |
1,199,100,000
GBP
|
— | — | — | — | — | — | — | — |
992,700,000
GBP
|
— | — | — | — | — | — | — | — | — | — |