v3.25.4
Derivative Financial Instruments (Narrative) (Details)
$ in Millions
1 Months Ended 12 Months Ended
Mar. 31, 2016
USD ($)
contract
Dec. 31, 2025
USD ($)
Dec. 31, 2024
USD ($)
Derivative Financial Instruments      
Increase (decrease) in derivative fair value   $ (0.4)  
Cash flow hedge ineffectiveness   $ 0.1  
Cash flow hedge ineffectiveness   Interest rate swap agreements are entered into with counterparties that meet established credit standards, and the Corporation believes that the credit risk inherent in these contracts is not significant at December 31, 2025.  
Interest Rate Swap Agreements      
Derivative Financial Instruments      
Number of interest rate swap contracts | contract 4    
Interest rate swap notional amount $ 30.0 $ 15.0  
Derivative, fixed interest rate   4.65%  
Interest rate swap fair value   $ 0.1 $ 0.5