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Derivative Financial Instruments and Hedging Activities - Information on Derivatives (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) derivative	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair value hedges:
Interest rate contracts fair value, Liability derivatives	$ 1,085	$ 1,912
Carrying Amounts of Hedged Assets	13,976	15,745
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Loans	939	1,753
Interest and fees on loans	91,612	84,674	$ 84,331
Fair value hedge | Interest income
Fair value hedges:
Increase (decrease) in value of designated interest rate swaps due to LIBOR interest rate movements	827	(734)	(964)
Payment on interest rate swaps	(369)	(360)	(90)
(Decrease) increase in value of hedged loans	(814)	809	938
Decrease in value of yield maintenance agreement	(11)	(12)	(13)
Net loss on derivatives recognized against interest income	(367)	(297)	$ (129)
Fair value hedge | Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Derivatives, accrued interest, interest rate swaps	$ 11
Interest rate swap | Fair value hedge | Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Number of derivative instruments | derivative	4
Interest rate swap | Fair value hedge | Designated as hedging instrument | Other assets
Fair value hedges:
Interest rate contracts notional amounts, Asset derivatives	$ 0	0
Interest rate swap | Fair value hedge | Designated as hedging instrument | Other liabilities
Fair value hedges:
Interest rate contracts notional amount, Liability derivatives	13,037	13,991
Interest rate contract | Fair value hedge | Designated as hedging instrument | Other assets
Fair value hedges:
Interest rate contracts fair value, Asset derivatives	0	0
Interest rate contract | Fair value hedge | Designated as hedging instrument | Other liabilities
Fair value hedges:
Interest rate contracts fair value, Liability derivatives	$ 1,085	$ 1,912

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