Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2022-03-31 |
As at 2021-03-31 |
As at 2020-03-31 |
|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | |||
| Property, plant and equipment [abstract] | |||
| Property, plant and equipment |
27,000,000
GBP
|
30,000,000
GBP
|
— |
| Investment property [abstract] | |||
| Investment property |
7,032,000,000
GBP
|
6,326,000,000
GBP
|
— |
| Investments in subsidiaries, joint ventures and associates reported in separate financial statements [abstract] | |||
| Investments in joint ventures reported in separate financial statements |
2,511,000,000
GBP
|
2,120,000,000
GBP
|
— |
| Trade and other non-current receivables [abstract] | |||
| Trade and other non-current receivables |
–
GBP
|
6,000,000
GBP
|
— |
| Miscellaneous non-current assets [abstract] | |||
| Non-current derivative financial assets |
97,000,000
GBP
|
135,000,000
GBP
|
— |
| Other non-current assets |
9,708,000,000
GBP
|
8,639,000,000
GBP
|
— |
| Trade and other current receivables [abstract] | |||
| Trade and other current receivables |
39,000,000
GBP
|
56,000,000
GBP
|
— |
| Cash and cash equivalents [abstract] | |||
| Cash and cash equivalents |
74,000,000
GBP
|
154,000,000
GBP
|
193,000,000
GBP
|
| Borrowings [abstract] | |||
| Non-current portion of non-current borrowings |
2,427,000,000
GBP
|
2,249,000,000
GBP
|
— |
| Current borrowings and current portion of non-current borrowings [abstract] | |||
| Current borrowings |
189,000,000
GBP
|
161,000,000
GBP
|
— |
| Non-current portion of non-current borrowings, by type [abstract] | |||
| Trade and other current payables [abstract] | |||
| Trade and other current payables |
245,000,000
GBP
|
219,000,000
GBP
|
— |
| Miscellaneous non-current liabilities [abstract] | |||
| Non-current derivative financial liabilities |
96,000,000
GBP
|
128,000,000
GBP
|
— |
| Other non-current liabilities |
152,000,000
GBP
|
128,000,000
GBP
|
— |
| Issued capital [abstract] | |||
| Issued capital |
234,000,000
GBP
|
234,000,000
GBP
|
— |
| Retained earnings [abstract] | |||
| Retained earnings |
4,959,000,000
GBP
|
4,154,000,000
GBP
|
— |
| Miscellaneous equity [abstract] | |||
| Merger reserve |
213,000,000
GBP
|
213,000,000
GBP
|
— |
| Net assets (liabilities) [abstract] | |||
| Assets |
9,842,000,000
GBP
|
8,875,000,000
GBP
|
— |
| Liabilities |
3,109,000,000
GBP
|
2,892,000,000
GBP
|
— |
| Assets (liabilities) |
6,733,000,000
GBP
|
5,983,000,000
GBP
|
— |
| Net current assets (liabilities) [abstract] | |||
| Current assets |
134,000,000
GBP
|
236,000,000
GBP
|
— |
| Current liabilities |
434,000,000
GBP
|
387,000,000
GBP
|
— |
| Assets less current liabilities [abstract] |