Statement Of Cash Flows [Abstract]
| Concept |
As at 2022-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
2022-01-01 to 2022-12-31 |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2021-01-01 to 2021-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||||||||||||
| Cash flows from (used in) operating activities [abstract] | |||||||||||||||
| Profit (loss) | — |
1,394,000,000
GBP
|
1,394,000,000
GBP
|
1,394,000,000
GBP
|
19,000,000
GBP
|
— |
1,365,000,000
GBP
|
1,384,000,000
GBP
|
1,365,000,000
GBP
|
452,000,000
GBP
|
— |
471,000,000
GBP
|
19,000,000
GBP
|
452,000,000
GBP
|
— |
| Adjustments to reconcile profit (loss) [abstract] | |||||||||||||||
| Adjustments for depreciation and amortisation expense | — | — |
296,000,000
GBP
|
— | — | — | — |
501,000,000
GBP
|
— | — | — |
562,000,000
GBP
|
— | — | — |
| Adjustments for impairment loss (reversal of impairment loss) recognised in profit or loss | — | — |
284,000,000
GBP
|
— | — | — | — |
228,000,000
GBP
|
— | — | — |
672,000,000
GBP
|
— | — | — |
| Adjustments for provisions | — | — |
419,000,000
GBP
|
— | — | — | — |
381,000,000
GBP
|
— | — | — |
273,000,000
GBP
|
— | — | — |
| Adjustments for unrealised foreign exchange losses (gains) | — | — |
1,383,000,000
GBP
|
— | — | — | — |
542,000,000
GBP
|
— | — | — |
410,000,000
GBP
|
— | — | — |
| Other adjustments for non-cash items | — | — |
1,497,000,000
GBP
|
— | — | — | — |
147,000,000
GBP
|
— | — | — |
267,000,000
GBP
|
— | — | — |
| Cash flows from (used in) operating activities | — | — |
2,970,000,000
GBP
|
— | — | — | — |
10,251,000,000
GBP
|
— | — | — |
18,918,000,000
GBP
|
— | — | — |
| Cash flows from (used in) investing activities [abstract] | |||||||||||||||
| Cash flows from (used in) investing activities | — | — |
198,000,000
GBP
|
— | — | — | — |
3,077,000,000
GBP
|
— | — | — |
6,636,000,000
GBP
|
— | — | — |
| Cash flows from (used in) financing activities [abstract] | |||||||||||||||
| Proceeds from issuing other equity instruments | — | — |
750,000,000
GBP
|
— | — | — | — |
210,000,000
GBP
|
— | — | — |
—
GBP
|
— | — | — |
| Payments of other equity instruments | — | — |
985,000,000
GBP
|
— | — | — | — |
210,000,000
GBP
|
— | — | — |
—
GBP
|
— | — | — |
| Payments of lease liabilities, classified as financing activities | — | — |
26,000,000
GBP
|
— | — | — | — |
25,000,000
GBP
|
— | — | — |
45,000,000
GBP
|
— | — | — |
| Cash flows from (used in) financing activities | — | — |
277,000,000
GBP
|
— | — | — | — |
10,753,000,000
GBP
|
— | — | — |
6,773,000,000
GBP
|
— | — | — |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes | — | — |
2,891,000,000
GBP
|
— | — | — | — |
2,575,000,000
GBP
|
— | — | — |
18,781,000,000
GBP
|
— | — | — |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||||||||||||
| Effect of exchange rate changes on cash and cash equivalents | — | — |
121,000,000
GBP
|
— | — | — | — |
18,000,000
GBP
|
— | — | — |
45,000,000
GBP
|
— | — | — |
| Cash and cash equivalents |
46,484,000,000
GBP
|
— | — | — | — |
49,254,000,000
GBP
|
— | — | — | — |
46,697,000,000
GBP
|
— | — | — |
27,871,000,000
GBP
|