Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2023-03-31 |
As at 2022-03-31 |
|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | ||
| Property, plant and equipment [abstract] | ||
| Property, plant and equipment |
478,500,000
GBP
|
710,600,000
GBP
|
| Intangible assets and goodwill [abstract] | ||
| Intangible assets other than goodwill [abstract] | ||
| Intangible assets other than goodwill |
140,800,000
GBP
|
176,700,000
GBP
|
| Goodwill |
781,400,000
GBP
|
783,400,000
GBP
|
| Investments accounted for using equity method [abstract] | ||
| Investments accounted for using equity method |
57,400,000
GBP
|
54,300,000
GBP
|
| Trade and other non-current receivables [abstract] | ||
| Non-current receivables due from related parties |
9,500,000
GBP
|
12,100,000
GBP
|
| Trade and other non-current receivables |
6,400,000
GBP
|
9,700,000
GBP
|
| Miscellaneous non-current assets [abstract] | ||
| Non-current net defined benefit asset |
94,800,000
GBP
|
300,900,000
GBP
|
| Non-current derivative financial assets |
2,600,000
GBP
|
–
GBP
|
| Non-current finance lease receivables |
22,200,000
GBP
|
24,100,000
GBP
|
| Trade and other current receivables [abstract] | ||
| Trade and other current receivables |
506,900,000
GBP
|
488,800,000
GBP
|
| Current prepayments and current accrued income including current contract assets [abstract] | ||
| Current accrued income including current contract assets [abstract] | ||
| Current contract assets |
322,500,000
GBP
|
299,300,000
GBP
|
| Categories of non-current financial assets [abstract] | ||
| Non-current financial assets |
7,300,000
GBP
|
10,000,000
GBP
|
| Classes of current inventories [abstract] | ||
| Current inventories |
126,800,000
GBP
|
142,700,000
GBP
|
| Classes of current inventories, alternative [abstract] | ||
| Cash and cash equivalents [abstract] | ||
| Cash and cash equivalents |
451,700,000
GBP
|
1,146,300,000
GBP
|
| Miscellaneous current assets [abstract] | ||
| Current derivative financial assets |
4,300,000
GBP
|
11,400,000
GBP
|
| Current finance lease receivables |
16,400,000
GBP
|
23,300,000
GBP
|
| Borrowings [abstract] | ||
| Non-current portion of non-current borrowings |
768,400,000
GBP
|
847,700,000
GBP
|
| Current borrowings and current portion of non-current borrowings [abstract] | ||
| Current borrowings |
19,600,000
GBP
|
863,400,000
GBP
|
| Non-current portion of non-current borrowings, by type [abstract] | ||
| Trade and other non-current payables [abstract] | ||
| Trade and other non-current payables |
900,000
GBP
|
1,000,000
GBP
|
| Trade and other current payables [abstract] | ||
| Current accruals and current deferred income including current contract liabilities [abstract] | ||
| Current deferred income including current contract liabilities [abstract] | ||
| Current contract liabilities [abstract] | ||
| Current contract liabilities |
616,400,000
GBP
|
518,300,000
GBP
|
| Trade and other current payables |
911,100,000
GBP
|
888,100,000
GBP
|
| Miscellaneous non-current liabilities [abstract] | ||
| Non-current net defined benefit liability |
156,200,000
GBP
|
109,300,000
GBP
|
| Non-current derivative financial liabilities |
53,300,000
GBP
|
59,300,000
GBP
|
| Miscellaneous current liabilities [abstract] | ||
| Current derivative financial liabilities |
12,800,000
GBP
|
34,800,000
GBP
|
| Issued capital [abstract] | ||
| Issued capital |
303,400,000
GBP
|
303,400,000
GBP
|
| Retained earnings [abstract] | ||
| Retained earnings |
1,568,800,000
GBP
|
1,241,400,000
GBP
|
| Net assets (liabilities) [abstract] | ||
| Assets |
3,309,900,000
GBP
|
4,600,700,000
GBP
|
| Liabilities |
2,939,000,000
GBP
|
3,899,200,000
GBP
|
| Net current assets (liabilities) [abstract] | ||
| Current assets |
1,437,700,000
GBP
|
2,137,200,000
GBP
|
| Current liabilities |
1,693,500,000
GBP
|
2,482,700,000
GBP
|
| Assets less current liabilities [abstract] |