Managed Investment Entities - Selected financial information related to CLOs (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Gains (losses) on change in fair value of assets/liabilities:
Assets	$ (69)	$ 80	$ (189)
Liabilities	30	(110)	168
Management fees paid to AFG	15	15	16
CLO earnings (losses) attributable to AFG Shareholders	(2)	4	7
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Investment in CLO tranches	$ 200	$ 165	$ 188

Earnings (losses) of variable interest entities attributable to AFG shareholders.

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- Definition

Gain (loss) on change in fair value of assets of variable interest entities.

+ References

No definition available.

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- Definition

Gain (loss) on change in fair value of liabilities of variable interest entities.

+ References

No definition available.

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- Definition

Gains losses on change in fair value of assets liabilities collateralized loan obligations.

+ References

No definition available.

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- Definition

Management fees paid by variable interest entities.

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No definition available.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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