Risk associated with risk of surrenders, expressed as a percentage, used as an input to measure fair value.

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability gain (loss) included in earnings on liabilities still outstanding.

+ References

No definition available.

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- Definition

Level Three Asset As Percentage Of Asset Measured At Fair Value.

+ References

No definition available.

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- Definition

Level three assets that were priced using non-binding broker quotes.

+ References

No definition available.

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- Definition

Number of internal investment professionals.

+ References

No definition available.

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- Definition

Number of stocks transferred from Level 1 to Level 2.

+ References

No definition available.

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- Definition

Number of stocks transferred from Level 2 to Level 1.

+ References

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- Definition

Percentage of Internally Developed Level 3 Assets to Total Shareholders' Equity

+ References

No definition available.

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- Definition

Percentage of Internally Developed Level Three Assets to Total Assets.

+ References

No definition available.

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- Definition

Percentage of level 3 assets that were priced using non-binding broker quotes.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (c)

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-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226008-175313

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Fair Value Measurements (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 professional stock	Mar. 31, 2013 stock
Fair Value Measurements (Textual) [Abstract]
AFG's internal investment professionals	20
Number of stocks transferred from Level 2 to Level 1	0	0
Level 3 assets as a percentage of total assets measured at fair value	3.00%
Percentage of level 3 assets that were priced using non-binding broker quotes	85.00%
Level 3 assets that were priced using non-binding broker quotes	$ 833
Percentage of internally developed Level 3 assets to total assets (are less than)	0.50%
Percentage of internally developed Level 3 assets to Shareholders' equity (are less than)	3.00%
Total realized/unrealized losses included in net income on liabilities still outstanding	4	(18)
Fixed-indexed annuities (embedded derivative) [Member]
Fair Value Measurements (Textual) [Abstract]
Fair value of derivatives in annuity benefits accumulated measured using a discounted cash flow approach	904
Fixed-indexed annuities (embedded derivative) [Member] \| Minimum [Member]
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	4.00%
Fixed-indexed annuities (embedded derivative) [Member] \| Maximum [Member]
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	16.00%
Fixed-indexed annuties (embedded derivative), majority of future years [Member] \| Minimum [Member]
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	6.00%
Fixed-indexed annuties (embedded derivative), majority of future years [Member] \| Maximum [Member]
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	12.00%
Perpetual preferred stocks [Member]
Fair Value Measurements (Textual) [Abstract]
Number of stocks transferred from Level 1 to Level 2	8
Fair value of assets transferred from Level 1 to Level 2	55
Number of stocks transferred from Level 2 to Level 1
Fair value of assets transferred from Level 2 to Level 1
Common stocks [Member]
Fair Value Measurements (Textual) [Abstract]
Number of stocks transferred from Level 1 to Level 2
Fair value of assets transferred from Level 1 to Level 2
Number of stocks transferred from Level 2 to Level 1
Fair value of assets transferred from Level 2 to Level 1
Redeemable preferred stocks [Member]
Fair Value Measurements (Textual) [Abstract]
Number of stocks transferred from Level 1 to Level 2
Fair value of assets transferred from Level 1 to Level 2
Number of stocks transferred from Level 2 to Level 1
Fair value of assets transferred from Level 2 to Level 1