Statement Of Cash Flows [Abstract]
| Concept |
2021-04-01 to 2022-03-31 |
As at 2022-03-31 |
As at 2021-03-31 |
2020-04-01 to 2021-03-31 |
As at 2020-03-31 |
|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||
| Cash flows from (used in) operating activities [abstract] | |||||
| Interest received, classified as operating activities |
–
GBP
|
— | — |
1,000,000
GBP
|
— |
| Income taxes paid (refund), classified as operating activities |
1,000,000
GBP
|
— | — |
1,000,000
GBP
|
— |
| Cash flows from (used in) operating activities |
49 0
GBP
|
— | — |
559,000,000
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||
| Purchase of property, plant and equipment, classified as investing activities |
–
GBP
|
— | — |
1,000,000
GBP
|
— |
| Cash flows from (used in) investing activities |
–
GBP
|
— | — |
1,000,000
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||
| Proceeds from issuing shares |
1,000,000
GBP
|
— | — |
1,000,000
GBP
|
— |
| Payments to acquire or redeem entity's shares |
5 4
GBP
|
— | — |
–
GBP
|
— |
| Proceeds from borrowings, classified as financing activities |
–
GBP
|
— | — |
395,000,000
GBP
|
— |
| Payments of lease liabilities, classified as financing activities |
4,000,000
GBP
|
— | — |
5,000,000
GBP
|
— |
| Dividends paid, classified as financing activities |
3 89
GBP
|
— | — |
33 8
GBP
|
— |
| Interest paid, classified as financing activities |
52,000,000
GBP
|
— | — |
4 6
GBP
|
— |
| Cash flows from (used in) financing activities |
4 98
GBP
|
— | — |
7,000,000
GBP
|
— |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes |
8,000,000
GBP
|
— | — |
553,000,000
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||
| Effect of exchange rate changes on cash and cash equivalents |
4,000,000
GBP
|
— | — |
2,000,000
GBP
|
— |
| Cash and cash equivalents | — |
2 12
GBP
|
2 16
GBP
|
— |
7 71
GBP
|