Investments - Components of the net unrealized gain on securities that is included in AOCI in the Balance Sheet (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Unrealized gain on:
Pretax		$ 1,165	$ 105
Deferred Tax		(245)	(22)
Net		920	83
Total fixed maturities
Unrealized gain on:
Pretax		2,169	160
Deferred Tax		(456)	(34)
Net		1,713	126
Fixed maturities — annuity segment
Unrealized gain on:
Pretax	[1]	1,777	101
Deferred Tax	[1]	(373)	(21)
Net	[1]	1,404	80
Fixed maturities — all other
Unrealized gain on:
Pretax		392	59
Deferred Tax		(83)	(13)
Net		309	46
Deferred policy acquisition costs — annuity segment
Unrealized gain on:
Pretax		(760)	(42)
Deferred Tax		160	9
Net		(600)	(33)
Annuity benefits accumulated
Unrealized gain on:
Pretax		(259)	(14)
Deferred Tax		54	3
Net		(205)	(11)
Unearned revenue
Unrealized gain on:
Pretax		15	1
Deferred Tax		(3)	0
Net		$ 12	$ 1

[1] Net unrealized gains on fixed maturity investments supporting AFG’s annuity benefits accumulated.