Acquisitions (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended			0 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Apr. 01, 2014 Summit Holding Southeast, Inc [Member]	Apr. 01, 2014 Summit Holding Southeast, Inc [Member]
Business Acquisition [Line Items]
Total purchase price	$ 267	$ 0		$ 259
Tangible assets acquired:
Cash and cash equivalents					1,078
Fixed maturities, available for sale					92
Recoverables from reinsurers					116
Agents’ balances and premiums receivable					41
Deferred tax assets, net					67	[1]
Other receivables					23
Other assets					11
Total tangible assets acquired					1,428
Liabilities acquired:
Unpaid losses and loss adjustment expenses					1,142
Unearned premiums					3
Payable to reinsurers					3
Other liabilities					66
Total liabilities acquired					1,214
Net tangible assets acquired, at fair value					214
Excess purchase price over net tangible assets acquired					45
Allocation of excess purchase price:
Intangible assets acquired					45	[2]
Deferred tax on intangible assets acquired					(15)	[1]
Goodwill	$ 200		$ 185		$ 15

[1] Included with AFG’s net deferred tax liabilities, which are included in Other liabilities in AFG’s Consolidated Balance Sheet.

[2] Included in Other assets in AFG’s Consolidated Balance Sheet.