Managed Investment Entities - Selected financial information related to CLOs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Gains (losses) on change in fair value of assets/liabilities:
Assets	$ (247)	$ 21	$ (304)	$ 67
Liabilities	232	(15)	284	(59)
Management fees paid to AFG	4	4	8	8
CLO earnings (losses) attributable to AFG shareholders	(12)	14	(14)	32
Variable interest entity, primary beneficiary | Continuing operations
Gains (losses) on change in fair value of assets/liabilities:
CLO earnings (losses) attributable to AFG shareholders	(12)	7	(14)	12
Variable interest entity, primary beneficiary | Net earnings from discontinued operations | Annuity subsidiaries
Gains (losses) on change in fair value of assets/liabilities:
CLO earnings (losses) attributable to AFG shareholders	$ 0	$ 7	$ 0	$ 20