Investments (Schedule of Securities Pledged by Contractual Maturity) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities Lending	$ 296	$ 298
Total gross secured borrowings	296	298
Corporate Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	279	288
Equity Securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	9	8
Foreign Government Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	8	2
Overnight and Continuous [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	296	298
Overnight and Continuous [Member] | Corporate Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	279	288
Overnight and Continuous [Member] | Equity Securities [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	9	8
Overnight and Continuous [Member] | Foreign Government Bonds [Member]
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Total gross secured borrowings	$ 8	$ 2