Statement Of Comprehensive Income [Abstract]
| Concept |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
2021-04-04 to 2022-04-02 |
2020-03-29 to 2021-04-03 |
2020-03-29 to 2021-04-03 |
2020-03-29 to 2021-04-03 |
2020-03-29 to 2021-04-03 |
2020-03-29 to 2021-04-03 |
2020-03-29 to 2021-04-03 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||
| Profit (loss) |
77,500,000
GBP
|
–
GBP
|
–
GBP
|
77,500,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
106,000,000
GBP
|
–
GBP
|
106,000,000
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 |
357,300,000
GBP
|
–
GBP
|
–
GBP
|
357,300,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
750,300,000
GBP
|
–
GBP
|
750,300,000
GBP
|
–
GBP
|
| Other comprehensive income |
249,100,000
GBP
|
–
GBP
|
–
GBP
|
249,100,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
609,200,000
GBP
|
–
GBP
|
609,200,000
GBP
|
–
GBP
|
| Comprehensive income |
326,600,000
GBP
|
–
GBP
|
–
GBP
|
326,600,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
503,200,000
GBP
|
–
GBP
|
503,200,000
GBP
|
–
GBP
|
| Comprehensive income attributable to [abstract] | ||||||||||||
| Comprehensive income, attributable to owners of parent | — | — | — |
326,600,000
GBP
|
— | — | — | — | — | — |
503,200,000
GBP
|
— |