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Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Income Taxes (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Income Tax Disclosure
Tax at statutory rate, percentage	21.00%	21.00%	21.00%	21.00%
United States
Income Tax Disclosure
Deferred tax assets valuation allowance	$ 0		$ 0		$ 0
Cincinnati Global
Income Tax Disclosure
Deferred tax assets valuation allowance	0		0		0
Cincinnati Global \| United States
Income Tax Disclosure
Operating loss carryforwards	0		0		0
Cincinnati Global \| United Kingdom
Income Tax Disclosure
Operating loss carryforwards	$ 59		$ 59		$ 78