Condensed Consolidated Balance Sheets - (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Fixed maturities securities at amortized cost	$ 38,392	$ 38,126
Marketable securities, fixed maturities, amortized cost	51	0
Equity securities at cost	889	820
Mortgage loans on real estate, commercial and consumer, allowance for credit loss	20	0
Allowance for uncollectible reinsurance	24	25
Allowance for uncollectible insurance receivables	33	32
Accumulated depreciation on property and equipment	211	215
Due to related parties	14	21
Due from related parties	$ 0	$ 21
Common stock, par value (in usd per share)	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	273,040,243	273,040,243
Common stock, shares outstanding (in shares)	271,377,196	271,412,591
Treasury stock, shares (in shares)	1,663,047	1,627,652