v3.26.3
Fair Value (Fair Value of Assets and Liabilities Measured on Recurring Basis) (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Dec. 31, 2025
Long-term Debt $ 1,385.7 $ 1,384.8
Long-term Line of Credit 0.0 0.0
Level 1 [Member]    
Total Assets 8.0 8.3
Level 2 [Member]    
Total Assets 0.0 0.0
Level 3 [Member]    
Total Assets 0.0 0.0
Fair Value [Member]    
Total Assets 8.0 8.3
Money Market Funds [Member] | Level 1 [Member]    
Investments, Fair Value Disclosure 0.4 0.8
Money Market Funds [Member] | Level 2 [Member]    
Investments, Fair Value Disclosure 0.0 0.0
Money Market Funds [Member] | Level 3 [Member]    
Investments, Fair Value Disclosure 0.0 0.0
Money Market Funds [Member] | Fair Value [Member]    
Investments, Fair Value Disclosure 0.4 0.8
Debt [Member] | Level 1 [Member]    
Debt 0.0 0.0
Debt [Member] | Level 2 [Member]    
Debt 1,238.1 1,273.2
Debt [Member] | Level 3 [Member]    
Debt 17.7 16.4
Debt [Member] | Fair Value [Member]    
Debt 1,255.8 1,289.6
Mutual Fund | Level 1 [Member]    
Investments, Fair Value Disclosure 7.6 7.5
Mutual Fund | Level 2 [Member]    
Investments, Fair Value Disclosure 0.0 0.0
Mutual Fund | Level 3 [Member]    
Investments, Fair Value Disclosure 0.0 0.0
Mutual Fund | Fair Value [Member]    
Investments, Fair Value Disclosure $ 7.6 $ 7.5