Investments - Components of the net unrealized gain on securities that is included in AOCI in the Balance Sheet (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Unrealized gain on:
Pretax		$ 1,028	$ 105
Deferred Tax		(216)	(22)
Net		812	83
Total fixed maturities
Unrealized gain on:
Pretax		1,802	160
Deferred Tax		(378)	(34)
Net		1,424	126
Fixed maturities — annuity segment
Unrealized gain on:
Pretax	[1]	1,461	101
Deferred Tax	[1]	(307)	(21)
Net	[1]	1,154	80
Fixed maturities — all other
Unrealized gain on:
Pretax		341	59
Deferred Tax		(71)	(13)
Net		270	46
Deferred policy acquisition costs — annuity segment
Unrealized gain on:
Pretax		(602)	(42)
Deferred Tax		126	9
Net		(476)	(33)
Annuity benefits accumulated
Unrealized gain on:
Pretax		(186)	(14)
Deferred Tax		39	3
Net		(147)	(11)
Unearned revenue
Unrealized gain on:
Pretax		14	1
Deferred Tax		(3)	0
Net		$ 11	$ 1

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