Investments (Commercial Mortgage Loans By Year Of Origination) (Details) - Commercial [Member] $ in Millions	Sep. 30, 2023 USD ($) item	Dec. 31, 2022 USD ($) item
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 984	$ 1,876
Amount originated in prior year	1,855	2,426
Amount originated 2 years prior	2,404	1,306
Amount originated 3 years prior	1,242	2,795
Amount originated 4 years prior	2,577	2,296
Amount originated 5 or more years prior	8,152	6,315
Total	17,214	17,014
Loan-to-value ratio, less than 65% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	936	1,769
Amount originated in prior year	1,766	2,354
Amount originated 2 years prior	2,340	1,289
Amount originated 3 years prior	1,231	2,685
Amount originated 4 years prior	2,485	2,225
Amount originated 5 or more years prior	7,999	6,184
Total	$ 16,757	$ 16,506
Ratio of originations in current year | item	1.87	2.06
Ratio of originations in prior year | item	2.06	3.05
Ratio of originations 2 years prior | item	3.36	3.00
Ratio of originations 3 years prior | item	3.20	2.18
Ratio of originations 4 years prior | item	2.45	2.17
Ratio of originations 5 or more years prior | item	2.42	2.44
Loan-to-value ratio, 65% to 74% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 48	$ 105
Amount originated in prior year	88	72
Amount originated 2 years prior	64	17
Amount originated 3 years prior	11	81
Amount originated 4 years prior	82	71
Amount originated 5 or more years prior	152	131
Total	$ 445	$ 477
Ratio of originations in current year | item	1.42	1.50
Ratio of originations in prior year | item	2.06	1.53
Ratio of originations 2 years prior | item	1.57	1.58
Ratio of originations 3 years prior | item	1.50	1.50
Ratio of originations 4 years prior | item	1.48	1.62
Ratio of originations 5 or more years prior | item	1.59	1.75
Loan-to-value ratio, 75% to 100% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year		$ 2
Amount originated in prior year	$ 1
Amount originated 3 years prior		29
Amount originated 4 years prior	10
Amount originated 5 or more years prior	1
Total	$ 12	$ 31
Ratio of originations in current year | item		1.45
Ratio of originations in prior year | item	1.13
Ratio of originations 3 years prior | item		1.58
Ratio of originations 4 years prior | item	2.33
Ratio of originations 5 or more years prior | item	1.67