Income Taxes (Schedule of Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Income Tax Disclosure [Abstract]
Loss, LAE and unearned premium reserves, net	$ 226.1	$ 211.0
Employee benefit plans	11.1	9.4
Investments, net	1.3	79.8
Other	11.6	14.9
Total deferred tax assets	250.1	315.1
Deferred acquisition costs	147.6	139.2
Software capitalization	19.2	1.7
Total deferred tax liabilities	166.8	140.9
Net deferred tax asset	$ 83.3	$ 174.2

Amount of deferred tax liability attributable to taxable temporary differences.

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