Segments of Operations (Details Textual) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2015 USD ($)		Jun. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) segment		Sep. 30, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of segments | segment						4
Other income		$ 40			$ 28	$ 177		$ 75
Earnings (losses) of managed investment entities attributable to noncontrolling interests	[1]	0			(29)	0		(47)
Other Lines [Member]
Segment Reporting Information [Line Items]
Special charges to increase asbestos and environmental reserves		67			24
Property and Casualty Insurance [Member]
Segment Reporting Information [Line Items]
Other income		2	[2]		4	$ 61	[2]	8
Property and Casualty Insurance [Member] | Real Estate Investment [Member]
Segment Reporting Information [Line Items]
Other income	[2]			$ 51
Other [Member]
Segment Reporting Information [Line Items]
Special charges to increase asbestos and environmental reserves		12			6
Write off of deferred debt issuance cost due to the retirement of debt		$ 4
Earnings (losses) of managed investment entities attributable to noncontrolling interests					$ (29)			$ (47)

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

[2] Includes pretax income of $51 million (before noncontrolling interest) from the sale of the Le Pavillon Hotel in the second quarter of 2015.