Investments - Analysis of Cost or Amortized Cost, Gross Unrealized Gains and Losses and Fair Value for Investments (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale
Total	$ 13,362	$ 12,979
Gross unrealized gain	92	61
Gross unrealized loss	776	908
Fixed maturities, at fair value	12,678	12,132
Corporate
Debt Securities, Available-for-sale
Total	7,568	7,412
Gross unrealized gain	49	37
Gross unrealized loss	526	580
Fixed maturities, at fair value	7,091	6,869
States, municipalities and political subdivisions
Debt Securities, Available-for-sale
Total	4,933	4,901
Gross unrealized gain	42	24
Gross unrealized loss	226	303
Fixed maturities, at fair value	4,749	4,622
Government-sponsored enterprises
Debt Securities, Available-for-sale
Total	390	186
Gross unrealized gain	1	0
Gross unrealized loss	4	3
Fixed maturities, at fair value	387	183
Commercial mortgage-backed
Debt Securities, Available-for-sale
Total	241	250
Gross unrealized gain	0	0
Gross unrealized loss	16	16
Fixed maturities, at fair value	225	234
United States government
Debt Securities, Available-for-sale
Total	199	196
Gross unrealized gain	0	0
Gross unrealized loss	4	5
Fixed maturities, at fair value	195	191
Foreign government
Debt Securities, Available-for-sale
Total	31	34
Gross unrealized gain	0	0
Gross unrealized loss	0	1
Fixed maturities, at fair value	$ 31	$ 33