v3.25.4
Income Taxes (Schedule Of Reasons Behind Differences In Computation Of Total Income Taxes) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Schedule of Reasons Behind Differences in Computation of Total Income Taxes [Line Items]      
Book income before income taxes $ 1,216.4 $ 1,002.8 $ 813.9
Tax expense (benefit) at statutory federal income tax rate, value $ 255.4 $ 210.6 $ 170.8
Tax expense (benefit) at statutory federal income tax rate, rate 21.00% 21.00% 21.00%
Increases (reductions) in taxes resulting from:      
State income taxes, net of federal income tax benefit, value $ 4.9 $ 11.7 $ 13.7
State income taxes, net of federal income tax benefit, rate 0.40% 1.20% 1.70%
Fines and penalties, value $ 5.5 $ 12.5 $ 5.3
Fines and penalties, rate 0.40% 1.20% 0.70%
State regulatory proceedings, rate 0.10% (0.80%) (0.90%)
Other adjustments, value $ (4.4) $ 2.5 $ (4.4)
Other adjustments, rate 0.30% 0.20% (0.50%)
Income Taxes $ 203.8 $ 158.1 $ 139.5
Income Taxes, rate 16.80% 15.80% 17.10%