Information on the swap contracts and the number of swaps

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Derivative Financial Instruments (Narrative) (Details) $ in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($) contract	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Derivative [Line Items]
Decrease in fair value of derivatives		$ 1.5
Cash flow hedge ineffectiveness		$ 0.4
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, 2022.
Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Interest rate swap notional amount	$ 30.0	$ 20.0
Number of interest rate swap contracts \| contract	4
Interest rate swap fair value asset, asset		$ 1.1
Interest rate swap fair value asset, liability			$ (0.5)