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Derivative Financial Instruments and Hedging Activities - Information on Derivatives (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) derivative	Dec. 31, 2018 USD ($)
Fair value hedges:
Interest rate contracts fair value, Asset derivatives	$ 0	$ 161
Interest rate contracts fair value, Liability derivatives	1,178	375
Carrying Amounts of Hedged Assets	17,900	17,917
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Loans	944	6
Interest and fees on loans	84,331	79,527
Fair value hedge
Fair value hedges:
Net hedge ineffectiveness gain (loss), derivatives	(39)	13
Fair value hedge | Interest income
Fair value hedges:
(Decrease) increase in value of designated interest rate swaps due to LIBOR interest rate movements	(964)	452
Payment on interest rate swaps	(90)	(149)
Increase (decrease) in value of hedged loans	938	(425)
Decrease in value of yield maintenance agreement	(13)	(14)
Net loss on derivatives recognized against interest income	(129)	(136)
Fair value hedge | Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Derivatives, accrued interest, interest rate swaps	$ 6	3
Interest rate swap | Fair value hedge | Designated as hedging instrument
Derivatives, Fair Value [Line Items]
Number of derivative instruments | derivative	5
Interest rate swap | Fair value hedge | Designated as hedging instrument | Other assets
Fair value hedges:
Interest rate contracts notional amounts, Asset derivatives	$ 0	8,895
Interest rate swap | Fair value hedge | Designated as hedging instrument | Other liabilities
Fair value hedges:
Interest rate contracts notional amount, Liability derivatives	16,956	9,016
Interest rate contract | Fair value hedge | Designated as hedging instrument | Other assets
Fair value hedges:
Interest rate contracts fair value, Asset derivatives	0	161
Interest rate contract | Fair value hedge | Designated as hedging instrument | Other liabilities
Fair value hedges:
Interest rate contracts fair value, Liability derivatives	$ 1,178	$ 375

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