v3.25.4
Income Taxes - Schedule of Temporary Differences That Give Rise to Net Deferred Income Tax Assets (Liabilities) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Deferred Income Tax Assets:    
Insurance Reserves $ 5.5 $ 0.0
Unearned Premium Reserves 51.5 52.8
Tax Capitalization of Policy Acquisition Costs 51.8 49.5
Payroll and Employee Benefit Accruals 29.9 34.7
Investments 118.4 147.6
Net Operating Loss and Credit Carryforwards 3.9 14.0
Other 60.4 45.9
Subtotal 321.4 344.5
Valuation Allowance (38.0) (38.7)
Total Deferred Income Tax Assets 283.4 305.8
Deferred Income Tax Liabilities:    
Insurance Reserves 0.0 39.5
Deferred Policy Acquisition Costs 137.9 132.3
Goodwill and Other Intangible Assets 35.5 35.0
Depreciable Assets 21.2 14.6
Other 2.5 4.4
Total Deferred Income Tax Liabilities 197.1 225.8
Net Deferred Income Tax (Assets) 86.3 80.0
Income Tax Contingency [Line Items]    
Net Deferred Income Tax (Assets) 86.3 80.0
Variable Interest Entity, Primary Beneficiary    
Deferred Income Tax Liabilities:    
Net Deferred Income Tax (Assets) 4.2 1.5
Income Tax Contingency [Line Items]    
Net Deferred Income Tax (Assets) $ 4.2 $ 1.5