Statement Of Changes In Net Assets Available For Benefits [Abstract]
| Concept |
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 |
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 |
|---|---|---|---|---|---|---|---|---|
| Statement of changes in net assets available for benefits [abstract] | ||||||||
| Reconciliation of changes in net assets available for benefits [abstract] | ||||||||
| Assets (liabilities) of benefit plan |
502,000,000
USD
|
— | — | — |
643,000,000
USD
|
— | — | — |
| Changes in net assets available for benefits [abstract] | ||||||||
| Investment income | — |
—
USD
|
139,000,000
USD
|
139,000,000
USD
|
— |
115,000,000
USD
|
—
USD
|
115,000,000
USD
|
| Tax expense (income) | — |
659,000,000
USD
|
5,271,000,000
USD
|
5,930,000,000
USD
|
— |
2,136,000,000
USD
|
346,000,000
USD
|
1,790,000,000
USD
|