Statement Of Comprehensive Income [Abstract]
| Concept |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2021-02-01 to 2022-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
2020-02-01 to 2021-01-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of comprehensive income [abstract] | ||||||||||||||||||
| Profit (loss) |
–
GBP
|
106,000,000
GBP
|
737,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
843,000,000
GBP
|
843,000,000
GBP
|
–
GBP
|
592,000,000
GBP
|
12,000,000
GBP
|
604,000,000
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
592,000,000
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 | — | — | — | — | — | — | — |
21,000,000
GBP
|
— | — | — | — | — | — | — | — |
68,000,000
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 | — | — | — | — | — | — | — |
18,000,000
GBP
|
— | — | — | — | — | — | — | — |
13,000,000
GBP
|
— |
| Other comprehensive income |
179,000,000
GBP
|
— | — |
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
163,000,000
GBP
|
16,000,000
GBP
|
–
GBP
|
44,000,000
GBP
|
— | — |
–
GBP
|
122,000,000
GBP
|
–
GBP
|
166,000,000
GBP
|
–
GBP
|
| Comprehensive income |
179,000,000
GBP
|
— | — |
–
GBP
|
–
GBP
|
–
GBP
|
–
GBP
|
680,000,000
GBP
|
859,000,000
GBP
|
–
GBP
|
636,000,000
GBP
|
— | — |
–
GBP
|
122,000,000
GBP
|
–
GBP
|
758,000,000
GBP
|
–
GBP
|