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

No definition available.

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- Definition

Fair Value Measurements.

+ 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

Financial liabilities on annuities in the payout phase that are contingent on the survival of the annuitant(s).

+ References

No definition available.

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- Definition

Number of internal investment professionals.

+ References

No definition available.

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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 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 liabilities 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 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

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-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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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=66048111&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.

+ References

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ 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 (c)(3)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Fair Value Measurements - Narrative (Details) $ in Millions	3 Months Ended
Fair Value Measurements - Narrative (Details) $ in Millions	Mar. 31, 2018 USD ($) professional	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Fair Value Measurements (Textual) [Abstract]
AFG's internal investment professionals \| professional	25
Fair Value of assets transferred from Level 1 to Level 2, during the first three months	$ 0
Fair Value of assets transferred from Level 2 to Level 1, during the first three months	$ 0
Level 3 assets as a percentage of total assets measured at fair value	6.00%
Percentage of level 3 assets that were priced using non-binding broker quotes	78.00%
Level 3 assets that were priced using non-binding broker quotes	$ 2,030
Fair value of equity securities transferred into Level 3	36	$ 57
Life contingent annuities	$ 209		$ 206
Maximum
Fair Value Measurements (Textual) [Abstract]
Percentage of internally developed Level 3 asset fair values to Shareholders' equity (are less than)	10.00%
Fixed-indexed annuties (embedded derivative), majority of future years \| Minimum
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 \| Maximum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	10.00%
Fixed-indexed annuities (embedded derivative)
Fair Value Measurements (Textual) [Abstract]
Fair value of derivatives in annuity benefits accumulated measured using a discounted cash flow approach	$ 2,550
Fixed-indexed annuities (embedded derivative) \| Minimum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	3.00%
Fixed-indexed annuities (embedded derivative) \| Maximum
Fair Value Measurements (Textual) [Abstract]
Unobservable input surrenders used in Level 3 fair value determination	23.00%
Equity securities
Fair Value Measurements (Textual) [Abstract]
Fair value of equity securities transferred into Level 3	$ 29	$ 0