Investments (Residential Mortgage Loans By Year Of Origination) (Details) - Residential [Member] - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	$ 359	$ 583
Amount originated in prior year	569	533
Amount originated 2 years prior	491	93
Amount originated 3 years prior	84	137
Amount originated 4 years prior	115	67
Amount originated 5 or more years prior	58
Total	1,676	1,413
Performing [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year	359	578
Amount originated in prior year	552	527
Amount originated 2 years prior	477	90
Amount originated 3 years prior	83	119
Amount originated 4 years prior	103	65
Amount originated 5 or more years prior	55
Total	1,629	1,379
Nonperforming [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Amount originated in current year		5
Amount originated in prior year	17	6
Amount originated 2 years prior	14	3
Amount originated 3 years prior	1	18
Amount originated 4 years prior	12	2
Amount originated 5 or more years prior	3
Total	$ 47	$ 34