Analysis Of Income And Expense [Abstract]
| Concept |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2021-05-01 to 2022-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
2020-05-01 to 2021-04-30 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Analysis of income and expense [abstract] | ||||||||||||||||||||||
| Revenue [abstract] | ||||||||||||||||||||||
| Revenue | — |
–
GBP
|
7,241,000,000
GBP
|
— | — | — | — | — | — | — |
7,241,000,000
GBP
|
— | — | — |
–
GBP
|
5,976,000,000
GBP
|
5,976,000,000
GBP
|
— | — | — | — | — |
| Material income and expense [abstract] | ||||||||||||||||||||||
| Finance income (cost) | — |
2,000,000
GBP
|
70,000,000
GBP
|
— | — | — | — | — | — | — |
72,000,000
GBP
|
— | — | — |
7,000,000
GBP
|
78,000,000
GBP
|
85,000,000
GBP
|
— | — | — | — | — |
| Operating expense | — |
37,000,000
GBP
|
6, 625
GBP
|
— | — | — | — | — | — | — |
6,662,000,000
GBP
|
— | — | — |
44,000,000
GBP
|
5,474,000,000
GBP
|
5,518,000,000
GBP
|
— | — | — | — | — |
| Expenses by nature [abstract] | ||||||||||||||||||||||
| Classes of employee benefits expense [abstract] | ||||||||||||||||||||||
| Employee benefits expense | — |
–
GBP
|
3,000,000
GBP
|
— | — | — | — | — | — | — |
3,000,000
GBP
|
— | — | — |
–
GBP
|
3,000,000
GBP
|
3,000,000
GBP
|
— | — | — | — | — |
| Miscellaneous other comprehensive income [abstract] | ||||||||||||||||||||||
| Other comprehensive income, before tax, exchange differences on translation of foreign operations and hedges of net investments in foreign operations [abstract] | ||||||||||||||||||||||
| Other comprehensive income, before tax, exchange differences on translation of foreign operations |
–
GBP
|
— | — |
–
GBP
|
–
GBP
|
40,000,000
GBP
|
–
GBP
|
–
GBP
|
4 0
GBP
|
–
GBP
|
40,000,000
GBP
|
–
GBP
|
95,000,000
GBP
|
–
GBP
|
— | — |
95,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
95,000,000
GBP
|
| Other comprehensive income, before tax, hedges of net investments in foreign operations |
–
GBP
|
— | — |
–
GBP
|
–
GBP
|
28,000,000
GBP
|
–
GBP
|
–
GBP
|
28,000,000
GBP
|
–
GBP
|
28,000,000
GBP
|
–
GBP
|
2,000,000
GBP
|
–
GBP
|
— | — |
2,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
2,000,000
GBP
|
| Share of profit (loss) of associates and joint ventures accounted for using equity method [abstract] | ||||||||||||||||||||||
| Share of profit (loss) of associates and joint ventures accounted for using equity method | — |
–
GBP
|
7,000,000
GBP
|
— | — | — | — | — | — | — |
7,000,000
GBP
|
— | — | — |
–
GBP
|
5,000,000
GBP
|
5,000,000
GBP
|
— | — | — | — | — |
| Income tax relating to components of other comprehensive income [abstract] | ||||||||||||||||||||||
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss | — | — | — | — | — | — | — | — | — | — |
14,000,000
GBP
|
— | — | — | — | — |
5,000,000
GBP
|
— | — | — | — | — |
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss | — | — | — | — | — | — | — | — | — | — |
162,000,000
GBP
|
— | — | — | — | — |
21,000,000
GBP
|
— | — | — | — | — |
| Income tax relating to components of other comprehensive income |
–
GBP
|
— | — |
–
GBP
|
14,000,000
GBP
|
176,000,000
GBP
|
–
GBP
|
–
GBP
|
1,000,000
GBP
|
163,000,000
GBP
|
176,000,000
GBP
|
–
GBP
|
1,000,000
GBP
|
20,000,000
GBP
|
— | — |
26,000,000
GBP
|
5,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
26,000,000
GBP
|
| Comprehensive income, continuing and discontinued operations [abstract] | ||||||||||||||||||||||
| Comprehensive income |
–
GBP
|
— | — |
–
GBP
|
334,000,000
GBP
|
869,000,000
GBP
|
–
GBP
|
–
GBP
|
14,000,000
GBP
|
549,000,000
GBP
|
869,000,000
GBP
|
–
GBP
|
9 8
GBP
|
92,000,000
GBP
|
— | — |
175,000,000
GBP
|
181,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
17 5
GBP
|
| Comprehensive income attributable to owners of parent, continuing and discontinued operations [abstract] | ||||||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — | — | — | — | — |
869,000,000
GBP
|
— | — | — | — | — |
175,000,000
GBP
|
— | — | — | — | — |
| Comprehensive income attributable to non-controlling interests, continuing and discontinued operations [abstract] | ||||||||||||||||||||||
| Comprehensive income, attributable to non-controlling interests | — | — | — | — | — | — | — | — | — | — |
–
GBP
|
— | — | — | — | — |
–
GBP
|
— | — | — | — | — |