Income Taxes (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of income taxes at the statutory rate and income taxes shown in the Statement of Earnings
Earnings before income taxes	$ 560	$ 689	$ 812
Income taxes at statutory rate	196	241	284
Effect of Change in valuation allowance	44	(1)	(7)
Effect of Losses of managed investment entities	9	23
Effect of Goodwill impairment charge		8
Effect of Subsidiaries not in AFG's tax return	5	6	8
Effect of Tax exempt interest	(23)	(16)	(10)
Effect of Other income tax reconciliation	9	5	7
Provision for income taxes as shown on the Statement of Earnings	$ 240	$ 266	$ 282

Income Tax Reconciliation Nondeductible Expense Losses Of Managed Investment Entities.

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- Definition

The portion of the difference 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 tax on the equity in earnings (losses) of less than 80%-owned subsidiaries not included in AFG's consolidated tax return.

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- Definition

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

+ References

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-Name Regulation S-X (SX)

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The portion of the difference between total income tax expense or benefit as reported in the Income Statement 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 changes in the valuation allowance for deferred tax assets in the period.

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- Definition

The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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- Definition

The portion of the difference 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 impairment losses under enacted tax laws.

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- Definition

The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting 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, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference 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 income that is exempt from income taxes under enacted tax laws.

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