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v3.25.4

Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Amount: |  |  |
Income tax expense at U.S. federal statutory tax rate | $ 177.2 | $ 112.9 | $ 8.7
Tax Jurisdiction of Domicile [Extensible Enumeration] | UNITED STATES | UNITED STATES | UNITED STATES
Adjustments for state income tax, nontaxable, nondeductible and other items, net of federal tax benefits as applicable | $ 5.9 |  |
Nondeductible expenses |  | $ 4.8 | $ 3.8
Stock-based compensation windfall benefit |  | (1.9) | (1.1)
Tax difference related to investment disposals and maturities |  | (1.2) | (1.3)
Change in uncertain tax positions |  | (1.0) | (0.9)
Current year federal tax credits |  | (0.9) | (0.7)
Dividend received deduction |  | (0.3) | (0.5)
Other, net |  | 0.1 | (0.4)
Total income tax expense | $ 183.1 | $ 112.5 | $ 7.6
Percentages: |  |  |
U.S. statutory federal income tax rate | 21.00% |  |
Adjustments for state income tax, nontaxable, nondeductible and other items, net of federal tax benefits as applicable | 0.70% |  |
Effective income tax rate | 21.70% | 20.90% | 18.50%

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