Investments (Commercial Mortgage Loans By Year Of Origination) (Details) - Commercial [Member]	Dec. 31, 2021 USD ($) item	Dec. 31, 2020 USD ($) item
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 2,520,000,000	$ 1,536,000,000
Amount originated in prior year	1,502,000,000	3,401,000,000
Amount originated 2 years prior	3,105,000,000	2,583,000,000
Amount originated 3 years prior	2,461,000,000	1,955,000,000
Amount originated 4 years prior	1,831,000,000	1,909,000,000
Amount originated 5 or more years prior	5,752,000,000	4,851,000,000
Total	17,171,000,000	16,235,000,000
Loan-to-value ratio, less than 65% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	2,384,000,000	1,504,000,000
Amount originated in prior year	1,358,000,000	3,141,000,000
Amount originated 2 years prior	2,917,000,000	2,382,000,000
Amount originated 3 years prior	2,274,000,000	1,786,000,000
Amount originated 4 years prior	1,655,000,000	1,713,000,000
Amount originated 5 or more years prior	5,554,000,000	4,710,000,000
Total	$ 16,142,000,000	$ 15,236,000,000
Ratio of originations in current year | item	3.04	2.86
Ratio of originations in prior year | item	3.03	2.25
Ratio of originations 2 years prior | item	2.15	2.16
Ratio of originations 3 years prior | item	2.13	2.34
Ratio of originations 4 years prior | item	2.33	2.37
Ratio of originations 5 or more years prior | item	2.41	2.38
Loan-to-value ratio, 65% to 74% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 136,000,000	$ 32,000,000
Amount originated in prior year	144,000,000	258,000,000
Amount originated 2 years prior	188,000,000	186,000,000
Amount originated 3 years prior	172,000,000	169,000,000
Amount originated 4 years prior	149,000,000	174,000,000
Amount originated 5 or more years prior	171,000,000	133,000,000
Total	$ 960,000,000	$ 952,000,000
Ratio of originations in current year | item	1.74	1.52
Ratio of originations in prior year | item	2.06	1.78
Ratio of originations 2 years prior | item	1.42	1.49
Ratio of originations 3 years prior | item	1.59	1.73
Ratio of originations 4 years prior | item	1.74	1.56
Ratio of originations 5 or more years prior | item	1.76	1.95
Loan-to-value ratio, 75% to 100% [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in prior year		$ 2,000,000
Amount originated 2 years prior		15,000,000
Amount originated 3 years prior	$ 15,000,000
Amount originated 4 years prior	27,000,000	22,000,000
Amount originated 5 or more years prior	27,000,000	8,000,000
Total	$ 69,000,000	$ 47,000,000
Ratio of originations in prior year | item		1.74
Ratio of originations 2 years prior | item		0.71
Ratio of originations 3 years prior | item	1.02
Ratio of originations 4 years prior | item	0.83	1.58
Ratio of originations 5 or more years prior | item	1.08	1.02