Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2025-03-31 |
As at 2024-03-31 |
As at 2023-03-31 |
|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | |||
| Property, plant and equipment [abstract] | |||
| Property, plant and equipment |
473,300,000
GBP
|
531,800,000
GBP
|
— |
| Intangible assets and goodwill [abstract] | |||
| Intangible assets other than goodwill [abstract] | |||
| Intangible assets other than goodwill |
293,900,000
GBP
|
321,800,000
GBP
|
— |
| Goodwill |
249,800,000
GBP
|
401,400,000
GBP
|
— |
| Investments accounted for using equity method [abstract] | |||
| Investments accounted for using equity method |
2,100,000
GBP
|
2,200,000
GBP
|
— |
| Miscellaneous non-current assets [abstract] | |||
| Non-current net defined benefit asset |
39,400,000
GBP
|
18,400,000
GBP
|
— |
| Trade and other current receivables [abstract] | |||
| Trade and other current receivables |
388,400,000
GBP
|
456,800,000
GBP
|
— |
| Classes of current inventories [abstract] | |||
| Current inventories |
70,700,000
GBP
|
89,200,000
GBP
|
— |
| Classes of current inventories, alternative [abstract] | |||
| Cash and cash equivalents [abstract] | |||
| Cash and cash equivalents |
290,600,000
GBP
|
231,000,000
GBP
|
151,200,000
GBP
|
| Trade and other non-current payables [abstract] | |||
| Other non-current payables |
8,400,000
GBP
|
11,600,000
GBP
|
— |
| Trade and other current payables [abstract] | |||
| Trade and other current payables |
597,500,000
GBP
|
654,700,000
GBP
|
— |
| Issued capital [abstract] | |||
| Issued capital |
5,500,000
GBP
|
5,700,000
GBP
|
— |
| Retained earnings [abstract] | |||
| Retained earnings |
456,800,000
GBP
|
742,300,000
GBP
|
— |
| Accumulated other comprehensive income [abstract] | |||
| Reserve of exchange differences on translation |
27,600,000
GBP
|
16,700,000
GBP
|
— |
| Reserve of cash flow hedges |
3,200,000
GBP
|
6,400,000
GBP
|
— |
| Miscellaneous equity [abstract] | |||
| Capital redemption reserve |
41,000,000
GBP
|
40,800,000
GBP
|
— |
| Net assets (liabilities) [abstract] | |||
| Assets |
1,828,400,000
GBP
|
2,106,200,000
GBP
|
— |
| Liabilities |
1,201,900,000
GBP
|
1,180,100,000
GBP
|
— |
| Assets (liabilities) |
626,500,000
GBP
|
926,100,000
GBP
|
— |
| Net current assets (liabilities) [abstract] | |||
| Current assets |
756,200,000
GBP
|
789,000,000
GBP
|
— |
| Current liabilities |
672,400,000
GBP
|
685,800,000
GBP
|
— |
| Assets less current liabilities [abstract] |