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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure
Tax at statutory rate (percentage):	21.00%	21.00%	21.00%
Release of unrecognized tax benefits during the year	$ 0	$ 0	$ 34
Income tax refund received	0	2	0
United States
Income Tax Disclosure
Operating Loss Carryforwards	0	0
Net deferred tax assets, valuation allowance	0	0
Cincinnati Global
Income Tax Disclosure
Net deferred tax assets, valuation allowance	0	0	$ 31	$ 53
Cincinnati Global \| United States
Income Tax Disclosure
Operating Loss Carryforwards	0	0
Cincinnati Global \| United Kingdom
Income Tax Disclosure
Operating Loss Carryforwards	$ 78	$ 100