Analysis Of Income And Expense [Abstract]
| Concept |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2021-04-01 to 2022-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
2020-04-01 to 2021-03-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Analysis of income and expense [abstract] | ||||||||||||
| Revenue [abstract] | ||||||||||||
| Revenue | — | — | — | — | — |
16,025,000,000
GBP
|
— | — | — | — | — |
15,435,000,000
GBP
|
| Material income and expense [abstract] | ||||||||||||
| Gains (losses) on disposals of investments [abstract] | ||||||||||||
| Gains (losses) on disposals of investments | — | — | — | — | — |
106,000,000
GBP
|
— | — | — | — | — |
1,000,000
GBP
|
| Gains (losses) on litigation settlements [abstract] | ||||||||||||
| Gains (losses) on litigation settlements | — | — | — | — | — |
42,000,000
GBP
|
— | — | — | — | — |
–
GBP
|
| Expenses by nature [abstract] | ||||||||||||
| Depreciation, amortisation and impairment loss (reversal of impairment loss) recognised in profit or loss [abstract] | ||||||||||||
| Depreciation and amortisation expense [abstract] | ||||||||||||
| Amortisation expense | — | — | — | — | — |
6,000,000
GBP
|
— | — | — | — | — |
10,000,000
GBP
|
| Disclosure of attribution of expenses by nature to their function [text block] | — | — | — | — | — | — | — | — | — | — | — | — |
| Disclosure of attribution of expenses by nature to their function [abstract] | ||||||||||||
| Disclosure of attribution of expenses by nature to their function [line items] | ||||||||||||
| Miscellaneous other comprehensive income [abstract] | ||||||||||||
| Other comprehensive income, net of tax, exchange differences on translation of foreign operations and hedges of net investments in foreign operations [abstract] | ||||||||||||
| Other comprehensive income, net of tax, exchange differences on translation of foreign operations |
–
GBP
|
–
GBP
|
–
GBP
|
80,000,000
GBP
|
–
GBP
|
80,000,000
GBP
|
–
GBP
|
1 62
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
1 62
GBP
|
| Other comprehensive income, net of tax, hedges of net investments in foreign operations |
–
GBP
|
–
GBP
|
–
GBP
|
2,000,000
GBP
|
–
GBP
|
2,000,000
GBP
|
–
GBP
|
12,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
12,000,000
GBP
|
| 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, hedges of net investments in foreign operations | — | — | — | — | — |
2,000,000
GBP
|
— | — | — | — | — |
12,000,000
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 | — | — | — | — | — |
35,000,000
GBP
|
— | — | — | — | — |
28,000,000
GBP
|
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss | — | — | — | — | — |
10,000,000
GBP
|
— | — | — | — | — |
–
GBP
|
| Income tax relating to components of other comprehensive income |
–
GBP
|
–
GBP
|
35,000,000
GBP
|
10,000,000
GBP
|
–
GBP
|
2 5
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
28,000,000
GBP
|
28,000,000
GBP
|
| Comprehensive income, continuing and discontinued operations [abstract] | ||||||||||||
| Comprehensive income |
–
GBP
|
–
GBP
|
41,000,000
GBP
|
47,000,000
GBP
|
–
GBP
|
88,000,000
GBP
|
–
GBP
|
1 42
GBP
|
–
GBP
|
–
GBP
|
92,000,000
GBP
|
50,000,000
GBP
|