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Derivative Financial Instruments and Hedging Activities - Information on Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Carrying Amounts of Hedged Assets	$ 14,401		$ 14,401		$ 15,745
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Loans	1,122		1,122		1,753
Interest and fees on loans	24,027	$ 21,776	66,117	$ 63,880
Fair value hedge | Interest income
Derivatives, Fair Value [Line Items]
Increase (decrease) in fair value of designated interest rate swaps due to LIBOR interest rate movements	97	152	646	(1,351)
Payment on interest rate swaps	(93)	(108)	(278)	(255)
Decrease (increase) in fair value hedging adjustment of hedged loans	(94)	(155)	(631)	1,374
Decrease in value of yield maintenance agreement	(3)	(3)	(9)	(9)
Net losses on fair value hedging relationships recognized in interest income	(93)	$ (114)	(272)	$ (241)
Fair value hedge | Designated as hedging instrument | Interest rate swap | Asset Derivatives
Derivatives, Fair Value [Line Items]
Interest rate contracts notional amount, asset derivatives	0		0		0
Interest rate contracts fair value, asset derivatives	0		0		0
Fair value hedge | Designated as hedging instrument | Interest rate swap | Liability Derivatives
Derivatives, Fair Value [Line Items]
Interest rate contracts notional amount, liability derivatives	13,280		13,280		13,991
Interest rate contracts fair value, liability derivatives	$ 1,266		$ 1,266		$ 1,912

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