Statement Of Changes In Equity [Abstract]
| Concept |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
2021-01-01 to 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 2021-12-31 |
As at 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 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
2020-01-01 to 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2020-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
As at 2019-12-31 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Statement of changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||
| Statement of changes in equity [line items] | |||||||||||||||||||||||||||||||||||||||
| Equity |
13,507,000,000
GBP
|
820,000,000
GBP
|
2,377,000,000
GBP
|
20,737,000,000
GBP
|
1,000,000
GBP
|
— |
192,000,000
GBP
|
85,000,000
GBP
|
14,000,000
GBP
|
20,727,000,000
GBP
|
10,000,000
GBP
|
— | — | — | — |
12,720,000,000
GBP
|
10,000,000
GBP
|
133,000,000
GBP
|
2,370,000,000
GBP
|
19,882,000,000
GBP
|
1,678,000,000
GBP
|
— |
63,000,000
GBP
|
9,000,000
GBP
|
2,225,000,000
GBP
|
— |
19,892,000,000
GBP
|
280,000,000
GBP
|
796,000,000
GBP
|
6,000,000
GBP
|
2,370,000,000
GBP
|
2,225,000,000
GBP
|
167,000,000
GBP
|
12,223,000,000
GBP
|
250,000,000
GBP
|
796,000,000
GBP
|
27,000,000
GBP
|
70,000,000
GBP
|
1,678,000,000
GBP
|
| Changes in equity [abstract] | |||||||||||||||||||||||||||||||||||||||
| Comprehensive income [abstract] | |||||||||||||||||||||||||||||||||||||||
| Profit (loss) | — | — | — | — | — | — | — | — | — | — | — | — |
2,907,000,000
GBP
|
— |
536,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Other comprehensive income | — | — | — | — | — | — | — | — | — | — | — | — |
351,000,000
GBP
|
— |
164,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Comprehensive income | — | — | — | — | — | — | — | — | — | — | — | — |
2,556,000,000
GBP
|
— |
372,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Issue of equity | — | — | — | — | — | — | — | — | — | — | — |
941,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — |
—
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) through share-based payment transactions, equity | — | — | — | — | — | — | — | — | — | — | — | — |
7,000,000
GBP
|
4,000,000
GBP
|
— | — | — | — | — | — | — |
45,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Increase (decrease) in equity | — | — | — | — | — |
365,000,000
GBP
|
— | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |