Managed Investment Entities (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Gains (losses) on change in fair value of assets/liabilities (a):
Assets	$ (14)	[1]	$ (2)	[1]	$ 3	[1]	$ 53	[1]
Liabilities	(14)	[1]	(19)	[1]	(39)	[1]	(103)	[1]
Management fees paid to AFG	4		4		8		8
CLO earnings (losses) attributable to (b):
AFG shareholders	7	[2]	5	[2]	18	[2]	10	[2]
Noncontrolling interests	$ (31)	[2]	$ (18)	[2]	$ (42)	[2]	$ (46)	[2]

[1] Included in Revenues in AFG’s Statement of Earnings.

[2] Included in Earnings before income taxes in AFG’s Statement of Earnings.