Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2023-03-31 |
As at 2022-03-31 |
As at 2021-03-31 |
|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | |||
| Property, plant and equipment [abstract] | |||
| Construction in progress |
13,900,000
GBP
|
15,200,000
GBP
|
— |
| Property, plant and equipment |
300,000
GBP
|
500,000
GBP
|
— |
| Investment property [abstract] | |||
| Investment property |
2,738,000,000
GBP
|
2,751,900,000
GBP
|
— |
| Investments accounted for using equity method [abstract] | |||
| Investments accounted for using equity method |
18,300,000
GBP
|
3,800,000
GBP
|
— |
| Trade and other current receivables [abstract] | |||
| Trade and other current receivables |
33,100,000
GBP
|
28,600,000
GBP
|
— |
| Cash and cash equivalents [abstract] | |||
| Cash and cash equivalents |
118,000,000
GBP
|
243,500,000
GBP
|
46,600,000
GBP
|
| Borrowings [abstract] | |||
| Current borrowings and current portion of non-current borrowings [abstract] | |||
| Current portion of non-current borrowings |
1,246,400,000
GBP
|
1,244,400,000
GBP
|
— |
| Trade and other current payables [abstract] | |||
| Trade and other current payables |
46,800,000
GBP
|
44,900,000
GBP
|
— |
| Issued capital [abstract] | |||
| Issued capital |
296,100,000
GBP
|
294,800,000
GBP
|
— |
| Retained earnings [abstract] | |||
| Retained earnings |
135,300,000
GBP
|
345,100,000
GBP
|
— |
| Miscellaneous equity [abstract] | |||
| Merger reserve |
231,600,000
GBP
|
231,200,000
GBP
|
— |
| Net assets (liabilities) [abstract] | |||
| Assets |
2,922,600,000
GBP
|
3,120,500,000
GBP
|
— |
| Liabilities |
1,335,100,000
GBP
|
1,330,900,000
GBP
|
— |
| Assets (liabilities) |
1,587,500,000
GBP
|
1,789,600,000
GBP
|
— |
| Net current assets (liabilities) [abstract] | |||
| Current assets |
151,500,000
GBP
|
348,500,000
GBP
|
— |
| Current liabilities |
77,800,000
GBP
|
75,100,000
GBP
|
— |
| Assets less current liabilities [abstract] |