Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2024-03-31 |
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 |
19,000,000
GBP
|
22,000,000
GBP
|
— |
| Investment property [abstract] | |||
| Investment property |
5,229,000,000
GBP
|
5,677,000,000
GBP
|
— |
| Investments in subsidiaries, joint ventures and associates reported in separate financial statements [abstract] | |||
| Investments in joint ventures reported in separate financial statements |
2,429,000,000
GBP
|
2,206,000,000
GBP
|
— |
| Miscellaneous non-current assets [abstract] | |||
| Non-current derivative financial assets |
79,000,000
GBP
|
144,000,000
GBP
|
— |
| Other non-current assets |
7,810,000,000
GBP
|
8,107,000,000
GBP
|
— |
| Trade and other current receivables [abstract] | |||
| Trade and other current receivables |
34,000,000
GBP
|
34,000,000
GBP
|
— |
| Cash and cash equivalents [abstract] | |||
| Cash and cash equivalents |
88,000,000
GBP
|
125,000,000
GBP
|
111,000,000
GBP
|
| Miscellaneous current assets [abstract] | |||
| Current derivative financial assets |
20,000,000
GBP
|
–
GBP
|
— |
| Borrowings [abstract] | |||
| Non-current portion of non-current borrowings |
2,202,000,000
GBP
|
1,865,000,000
GBP
|
— |
| Current borrowings and current portion of non-current borrowings [abstract] | |||
| Current borrowings |
10,000,000
GBP
|
402,000,000
GBP
|
— |
| Non-current portion of non-current borrowings, by type [abstract] | |||
| Trade and other current payables [abstract] | |||
| Trade and other current payables |
260,000,000
GBP
|
282,000,000
GBP
|
— |
| Miscellaneous non-current liabilities [abstract] | |||
| Non-current derivative financial liabilities |
56,000,000
GBP
|
67,000,000
GBP
|
— |
| Other non-current liabilities |
121,000,000
GBP
|
145,000,000
GBP
|
— |
| Issued capital [abstract] | |||
| Issued capital |
235,000,000
GBP
|
234,000,000
GBP
|
— |
| Retained earnings [abstract] | |||
| Retained earnings |
3,528,000,000
GBP
|
3,742,000,000
GBP
|
— |
| Miscellaneous equity [abstract] | |||
| Merger reserve |
213,000,000
GBP
|
213,000,000
GBP
|
— |
| Net assets (liabilities) [abstract] | |||
| Assets |
7,974,000,000
GBP
|
8,290,000,000
GBP
|
— |
| Liabilities |
2,662,000,000
GBP
|
2,765,000,000
GBP
|
— |
| Assets (liabilities) |
5,312,000,000
GBP
|
5,525,000,000
GBP
|
— |
| Net current assets (liabilities) [abstract] | |||
| Current assets |
164,000,000
GBP
|
183,000,000
GBP
|
— |
| Current liabilities |
278,000,000
GBP
|
684,000,000
GBP
|
— |
| Assets less current liabilities [abstract] |