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 |
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) |
–
GBP
|
–
GBP
|
–
GBP
|
230 0
GBP
|
–
GBP
|
–
GBP
|
230. 0
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
125 5
GBP
|
–
GBP
|
125,500,000
GBP
|
–
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 |
–
GBP
|
–
GBP
|
–
GBP
|
21 8
GBP
|
–
GBP
|
–
GBP
|
21,800,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
22,500,000
GBP
|
–
GBP
|
22,500,000
GBP
|
–
GBP
|
| Components of other comprehensive income that will be reclassified to profit or loss, before tax [abstract] | ||||||||||||||
| Exchange differences on translation [abstract] | ||||||||||||||
| Other comprehensive income, before tax, exchange differences on translation of foreign operations | — | — | — | — | — | — |
21,800,000
GBP
|
— | — | — | — | — |
42,400,000
GBP
|
— |
| Cash flow hedges [abstract] | ||||||||||||||
| Other comprehensive income, before tax, cash flow hedges | — | — | — | — | — | — |
1,400,000
GBP
|
— | — | — | — | — |
4. 5
GBP
|
— |
| Hedges of net investment in foreign operations [abstract] | ||||||||||||||
| Other comprehensive income, before tax, hedges of net investments in foreign operations |
–
GBP
|
–
GBP
|
100,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
100,000
GBP
|
2,200,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
2,200,000
GBP
|
–
GBP
|
| Share of other comprehensive income of associates and joint ventures accounted for using equity method that will be reclassified to profit or loss, before tax | — | — | — | — | — | — |
100,000
GBP
|
— | — | — | — | — |
0. 1
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 | — | — | — | — | — | — |
900,000
GBP
|
— | — | — | — | — |
4,300,000
GBP
|
— |
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss [abstract] | ||||||||||||||
| Income tax relating to components of other comprehensive income that will be reclassified to profit or loss | — | — | — | — | — | — |
300,000
GBP
|
— | — | — | — | — |
1,000,000
GBP
|
— |
| Other comprehensive income | — | — | — | — | — | — |
43,900,000
GBP
|
— | — | — | — | — |
64,200,000
GBP
|
— |
| Comprehensive income |
–
GBP
|
–
GBP
|
21,900,000
GBP
|
250 9
GBP
|
–
GBP
|
1,100,000
GBP
|
2 73.9
GBP
|
42,500,000
GBP
|
–
GBP
|
–
GBP
|
107 3
GBP
|
3,500,000
GBP
|
61,300,000
GBP
|
–
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — | — | — | — |
273,900,000
GBP
|
— | — | — | — | — |
61,300,000
GBP
|
— |