Statement Of Changes In Net Assets Available For Benefits [Abstract]
| Concept |
2020-01-01 to 2020-12-31 |
2019-01-01 to 2019-12-31 |
|---|---|---|
| Statement of changes in net assets available for benefits [abstract] | ||
| Reconciliation of changes in net assets available for benefits [abstract] | ||
| Changes in net assets available for benefits [abstract] | ||
| Other income |
290,000,000
USD
|
12,000,000
USD
|
| Tax expense (income) |
407,000,000
USD
|
458,000,000
USD
|