Derivative Financial Instruments and Hedging Activities - Information on Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Carrying Amounts of Hedged Assets	$ 18,535		$ 18,535		$ 17,900
Cumulative Amount of Fair Value Hedging Adjustment Included in the Carrying Amount of the Hedged Loans	2,318		2,318		944
Interest and fees on loans	21,776	$ 21,525	63,880	$ 63,208
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	152	(485)	(1,351)	(1,389)
Payment on interest rate swaps	(108)	(23)	(255)	(49)
(Decrease) increase in value of hedged loans	(155)	424	1,374	1,359
Decrease in value of yield maintenance agreement	(3)	(3)	(9)	(10)
Net losses on fair value hedging relationships recognized in interest income	(114)	$ (87)	(241)	$ (89)
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	16,218		16,218		16,956
Interest rate contracts fair value, liability derivatives	$ 2,529		$ 2,529		$ 1,178

Increase (Decrease) in value of yield maintenance agreement recognized against interest income.

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Payment on interest rate swaps recorded in interest income.

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Nominal or face amount used to calculate payments on the derivative asset.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Nominal or face amount used to calculate payments on the derivative liability.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of asset hedged in fair value hedging relationship.

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Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk.

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Amount of unrealized gain (loss) included in earnings related to the fair value of the hedged item in an interest rate fair value hedge, offset by the gain (loss) on the hedging instrument to the extent that the fair value hedge is determined to be effective.

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Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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