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) |
151,000,000
GBP
|
19,000,000
GBP
|
–
GBP
|
–
GBP
|
151,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
170,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
79,000,000
GBP
|
–
GBP
|
–
GBP
|
68,000,000
GBP
|
–
GBP
|
11,000,000
GBP
|
68,000,000
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 remeasurements of defined benefit plans | — | — | — | — | — | — | — | — | — |
90,000,000
GBP
|
— | — | — | — | — |
153,000,000
GBP
|
— | — | — | — | — | — |
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss [abstract] | ||||||||||||||||||||||
| Income tax relating to components of other comprehensive income that will not be reclassified to profit or loss | — | — | — | — | — | — | — | — | — |
16,000,000
GBP
|
— | — | — | — | — |
26,000,000
GBP
|
— | — | — | — | — | — |
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss [abstract] | ||||||||||||||||||||||
| Income tax relating to cash flow hedges included in other comprehensive income | — | — | — | — | — | — | — | — | — |
2,000,000
GBP
|
— | — | — | — | — |
–
GBP
|
— | — | — | — | — | — |
| Other comprehensive income |
107,000,000
GBP
|
11,000,000
GBP
|
–
GBP
|
1 74
GBP
|
77,000,000
GBP
|
4,000,000
GBP
|
–
GBP
|
6,000,000
GBP
|
–
GBP
|
118,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
237,000,000
GBP
|
–
GBP
|
108,000,000
GBP
|
–
GBP
|
–
GBP
|
1 24
GBP
|
–
GBP
|
5,000,000
GBP
|
113,000,000
GBP
|
| Comprehensive income |
258,000,000
GBP
|
30,000,000
GBP
|
–
GBP
|
1 74
GBP
|
74,000,000
GBP
|
4,000,000
GBP
|
–
GBP
|
6,000,000
GBP
|
–
GBP
|
288,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
237,000,000
GBP
|
–
GBP
|
29,000,000
GBP
|
–
GBP
|
–
GBP
|
192,000,000
GBP
|
–
GBP
|
16,000,000
GBP
|
45,000,000
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — | — | — | — |
258,000,000
GBP
|
— | — | — | — | — |
45,000,000
GBP
|
— | — | — | — | — | — |
| Comprehensive income, attributable to non-controlling interests | — | — | — | — | — | — | — | — | — |
30,000,000
GBP
|
— | — | — | — | — |
16,000,000
GBP
|
— | — | — | — | — | — |