Investments (Details) - Impairment Charges - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment Information
Fixed maturities credit impairment charges	$ 15	$ 4	$ 1
Other investments credit impairment charges	40	0	0
Total investments credit impairment charges	55	4	1
U.S. Treasury securities and obligations of U.S. government and government agencies and authorities [Member]
Investment Information
Fixed maturities credit impairment charges	0	0	0
Obligations of states, municipalities and political subdivisions [Member]
Investment Information
Fixed maturities credit impairment charges	0	0	0
Debt securities issued by foreign governments [Member]
Investment Information
Fixed maturities credit impairment charges	0	0	0
Mortgage-backed securities, collateralized mortgage obligations and pass-through securities [Member]
Investment Information
Fixed maturities credit impairment charges	0	0	0
All other corporate bonds [Member]
Investment Information
Fixed maturities credit impairment charges	15	4	1
Redeemable preferred stock [Member]
Investment Information
Fixed maturities credit impairment charges	$ 0	$ 0	$ 0