Income Taxes - Narrative (Details) £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2022 GBP (£)
Income Tax Reconciliation [Line Items]
Statutory rate of income taxes	21.00%	21.00%	21.00%
Income tax expense (benefit)	$ 225	$ 254	$ 25
Effective income tax rate reconciliation, percent, excluding the impact of the sale of subsidiaries			28.00%
Income (losses) subject to tax in foreign jurisdictions	64	33	$ (131)
Amount of expense for penalties related to a tax position	0	0	0
Cash payments for income taxes	242	212	179
Amount unutilized
Income Tax Reconciliation [Line Items]
Operating loss carryforwards	43
Neon Capital Limited
Income Tax Reconciliation [Line Items]
Income tax expense (benefit)			(72)
Income tax benefit, portion attributable to current taxes payable			(65)
AFG
Income Tax Reconciliation [Line Items]
Income tax expense (benefit)	225	360	127
Interest included in tax provision			$ 0
Income tax penalties accrued	0	0
Maximum | AFG
Income Tax Reconciliation [Line Items]
Unrecognized tax benefits that would impact the effective tax rate	1	1
Interest included in tax provision	1	1
Interest on income taxes accrued	1	$ 1
United Kingdom
Income Tax Reconciliation [Line Items]
Operating loss carryforwards	$ 36			£ 30