Investments (Commercial Mortgage Loans By Year Of Origination) (Details) - Commercial [Member] $ in Millions	Mar. 31, 2023 USD ($) item	Dec. 31, 2022 USD ($) item
Financing Receivable, Credit Quality Indicator [Line Items]
Originated in current year	$ 155	$ 1,876
Originated in prior year	1,867	2,407
Originated in two years prior	2,400	1,297
Originated in three years prior	1,289	2,753
Originated in four years prior	2,741	2,289
Originated in five years prior and prior	8,477	6,301
Total	16,929	16,923
Loan-to-value ratio, less than 65% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Originated in current year	155	1,769
Originated in prior year	1,769	2,335
Originated in two years prior	2,330	1,280
Originated in three years prior	1,275	2,643
Originated in four years prior	2,630	2,222
Originated in five years prior and prior	8,177	6,170
Total	$ 16,336	$ 16,419
Originated in current year | item	1.61	2.06
Originated in prior year | item	2.06	3.05
Originated in two years prior | item	3.05	2.99
Originated in three years prior | item	2.85	2.17
Originated in four years prior | item	2.21	2.17
Originated in five years prior and prior | item	2.40	2.44
Loan-to-value ratio, 65% to 75% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Originated in current year		$ 105
Originated in prior year	$ 97	72
Originated in two years prior	70	17
Originated in three years prior	14	81
Originated in four years prior	93	67
Originated in five years prior and prior	217	131
Total	$ 491	$ 473
Originated in current year | item		1.50
Originated in prior year | item	2.02	1.53
Originated in two years prior | item	1.51	1.58
Originated in three years prior | item	1.54	1.50
Originated in four years prior | item	1.50	1.62
Originated in five years prior and prior | item	1.54	1.75
Loan-to-value ratio, 75% to 100% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Originated in current year		$ 2
Originated in prior year	$ 1
Originated in three years prior		29
Originated in four years prior	18
Originated in five years prior and prior	83
Total	$ 102	$ 31
Originated in current year | item		1.45
Originated in prior year | item	1.13
Originated in three years prior | item		1.58
Originated in four years prior | item	1.43
Originated in five years prior and prior | item	1.33