Consolidated Balance Sheet Parentheticals (Unaudited at June 30, 2020) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Fixed maturities, available for sale, amortized cost	$ 65,430	$ 65,281
Fixed maturities, available for sale, allowance for expected credit losses	8	0
Equity securities, cost	378	376
Premiums receivable, allowance for expected credit losses	94	49
Reinsurance recoverables, allowance for estimated uncollectible reinsurance	156	92
Contractholder receivables, allowance for expected credit losses	$ 22	$ 20
Common stock, shares authorized (in shares)	1,750.0	1,750.0
Common stock, shares issued (in shares)	253.2	255.5
Common stock, shares outstanding (in shares)	253.2	255.5
Treasury stock, at cost (in shares)	525.9	522.1