Statement Of Comprehensive Income [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 |
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 |
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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||||||||||||
| Profit (loss) |
958,000,000
GBP
|
–
GBP
|
2,000,000
GBP
|
958,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
960,000,000
GBP
|
257,000,000
GBP
|
703,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
178,000,000
GBP
|
1,261,000,000
GBP
|
1,083,000,000
GBP
|
–
GBP
|
–
GBP
|
1,031,000,000
GBP
|
–
GBP
|
52,000,000
GBP
|
1,031,000,000
GBP
|
| Other comprehensive income [abstract] | ||||||||||||||||||||||
| Components of other comprehensive income that will not be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||||||
| Other comprehensive income, before tax, gains (losses) on revaluation of property, plant and equipment, right-of-use assets and intangible assets | — | — | — | — | — | — | — |
–
GBP
|
— | — | — |
–
GBP
|
1,000,000
GBP
|
— | — |
1,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
1,000,000
GBP
|
| Other comprehensive income that will not be reclassified to profit or loss, before tax | — | — | — | — | — | — | — |
–
GBP
|
— | — | — | — | — | — | — |
14,000,000
GBP
|
— | — | — | — | — | — |
| Components of other comprehensive income that will be reclassified to profit or loss, before tax [abstract] | ||||||||||||||||||||||
| Exchange differences on translation [abstract] | ||||||||||||||||||||||
| Reclassification adjustments on exchange differences on translation of foreign operations, before tax |
12,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
12,000,000
GBP
|
12,000,000
GBP
|
— | — |
–
GBP
|
— | — | — | — |
–
GBP
|
— | — | — | — | — | — |
| Cash flow hedges [abstract] | ||||||||||||||||||||||
| Gains (losses) on cash flow hedges, before tax | — | — | — | — | — | — | — |
1,000,000
GBP
|
— | — | — | — | — | — | — |
3,000,000
GBP
|
— | — | — | — | — | — |
| Other comprehensive income |
11,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
12,000,000
GBP
|
11,000,000
GBP
|
— | — |
1,000,000
GBP
|
–
GBP
|
24,000,000
GBP
|
— | — |
5,000,000
GBP
|
–
GBP
|
–
GBP
|
1 7
GBP
|
2,000,000
GBP
|
–
GBP
|
5,000,000
GBP
|
| Comprehensive income |
947,000,000
GBP
|
–
GBP
|
2,000,000
GBP
|
958,000,000
GBP
|
–
GBP
|
–
GBP
|
12,000,000
GBP
|
949,000,000
GBP
|
— | — |
1,000,000
GBP
|
–
GBP
|
24,000,000
GBP
|
— | — |
1,088,000,000
GBP
|
–
GBP
|
–
GBP
|
1,014,000,000
GBP
|
2,000,000
GBP
|
52,000,000
GBP
|
1,036,000,000
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — | — |
947,000,000
GBP
|
— | — | — | — | — | — | — |
1,036,000,000
GBP
|
— | — | — | — | — | — |
| Comprehensive income, attributable to non-controlling interests | — | — | — | — | — | — | — |
2,000,000
GBP
|
— | — | — | — | — | — | — |
52,000,000
GBP
|
— | — | — | — | — | — |