Derivatives - Gain (loss) included in the Statement of Earnings for changes in the fair value of derivatives that do not qualify for hedge accounting (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (61)	$ (106)	$ (103)
MBS with embedded derivatives | Realized gains (losses) on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(3)	10	(7)
Public company warrants | Realized gains (losses) on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	0	(1)	(3)
Fixed-indexed and variable-indexed annuities (embedded derivative) | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(283)	(919)	204
Equity index call options | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	223	804	(298)
Equity index put options | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	3	2	(1)
Reinsurance contract (embedded derivative) | Net investment income
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (1)	$ (2)	$ 2