Managed Investment Entities - Selected financial information related to CLOs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Gains (losses) on change in fair value of assets/liabilities:
Assets	$ 144	$ (267)	$ 69
Liabilities	(117)	236	(59)
Management fees paid to AFG	16	17	16
CLO earnings (losses) attributable to AFG Shareholders	27	(10)	40
Variable interest entity, primary beneficiary | Continuing operations
Gains (losses) on change in fair value of assets/liabilities:
CLO earnings (losses) attributable to AFG Shareholders	27	(10)	20
Variable interest entity, primary beneficiary | Net earnings (loss) from discontinued operations | Annuity subsidiaries
Gains (losses) on change in fair value of assets/liabilities:
CLO earnings (losses) attributable to AFG Shareholders	$ 0	$ 0	$ 20