Investments (Commercial Mortgage Loans By Year Of Origination) (Details) - Commercial [Member]	Dec. 31, 2022 USD ($) item	Dec. 31, 2021 USD ($) item
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 1,876,000,000	$ 2,520,000,000
Amount originated in prior year	2,426,000,000	1,502,000,000
Amount originated 2 years prior	1,306,000,000	3,105,000,000
Amount originated 3 years prior	2,795,000,000	2,461,000,000
Amount originated 4 years prior	2,296,000,000	1,831,000,000
Amount originated 5 or more years prior	6,315,000,000	5,752,000,000
Total	17,014,000,000	17,171,000,000
Loan-to-value ratio, less than 65% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	1,769,000,000	2,384,000,000
Amount originated in prior year	2,354,000,000	1,358,000,000
Amount originated 2 years prior	1,289,000,000	2,917,000,000
Amount originated 3 years prior	2,685,000,000	2,274,000,000
Amount originated 4 years prior	2,225,000,000	1,655,000,000
Amount originated 5 or more years prior	6,184,000,000	5,554,000,000
Total	$ 16,506,000,000	$ 16,142,000,000
Ratio of originations in current year | item	2.06	3.04
Ratio of originations in prior year | item	3.05	3.03
Ratio of originations 2 years prior | item	3.00	2.15
Ratio of originations 3 years prior | item	2.18	2.13
Ratio of originations 4 years prior | item	2.17	2.33
Ratio of originations 5 or more years prior | item	2.44	2.41
Loan-to-value ratio, 65% to 74% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 105,000,000	$ 136,000,000
Amount originated in prior year	72,000,000	144,000,000
Amount originated 2 years prior	17,000,000	188,000,000
Amount originated 3 years prior	81,000,000	172,000,000
Amount originated 4 years prior	71,000,000	149,000,000
Amount originated 5 or more years prior	131,000,000	171,000,000
Total	$ 477,000,000	$ 960,000,000
Ratio of originations in current year | item	1.50	1.74
Ratio of originations in prior year | item	1.53	2.06
Ratio of originations 2 years prior | item	1.58	1.42
Ratio of originations 3 years prior | item	1.50	1.59
Ratio of originations 4 years prior | item	1.62	1.74
Ratio of originations 5 or more years prior | item	1.75	1.76
Loan-to-value ratio, 75% to 100% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 2,000,000
Amount originated 3 years prior	29,000,000	$ 15,000,000
Amount originated 4 years prior		27,000,000
Amount originated 5 or more years prior		27,000,000
Total	$ 31,000,000	$ 69,000,000
Ratio of originations in current year | item	1.45
Ratio of originations 3 years prior | item	1.58	1.02
Ratio of originations 4 years prior | item		0.83
Ratio of originations 5 or more years prior | item		1.08