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	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	$ (35)	$ (45)	$ (42)	$ (106)
MBS with embedded derivatives | Realized gains on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	(3)	3	(3)	4
Public company warrants | Realized gains on securities
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	0	1	0	(1)
Fixed-indexed annuities (embedded derivative) | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	(112)	(62)	(259)	(79)
Equity index call options | Annuity benefits
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	81	16	222	(24)
Reinsurance contracts (embedded derivative) | Net investment income
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Derivative	$ (1)	$ (3)	$ (2)	$ (6)