The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles and enacted tax laws.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32698-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

Name:	us-gaap_IncomeTaxReconciliationNondeductibleExpense
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Income Taxes (Details) (USD $) In Millions	3 Months Ended		6 Months Ended
Income Taxes (Details) (USD $) In Millions	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Income Taxes (Textuals) [Abstract]
AFG's liability for uncertain tax positions			$ 0
Variable Interest Entity, Primary Beneficiary [Member]
Income Tax Reconciliation [Line Items]
Non-deductible losses of managed investment entities	$ 20	$ 13	$ 55	$ 33