Off-Balance-Sheet Financial Instruments and Concentrations of Credit Risk (Details)	12 Months Ended
Dec. 31, 2019 USD ($) derivative	Dec. 31, 2018 USD ($)
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet financial instruments	$ 195,577,000	$ 166,312,000
Designated as Hedging Instrument \| Interest Rate Swap \| Cash Flow Hedging
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Number of derivative instruments (derivative) \| derivative	7
Notional Amount	$ 150,000,000	125,000,000
Unrealized gain on derivative	97,000
Designated as Hedging Instrument \| Customer Loan Interest Swap \| Cash Flow Hedging
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional Amount	32,748,000
Unused lines, collateralized by residential real estate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet financial instruments	81,193,000	83,421,000
Other unused commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet financial instruments	90,186,000	60,033,000
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet financial instruments	4,496,000	3,590,000
Commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet financial instruments	$ 19,702,000	$ 19,268,000

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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The number of derivative instruments of a particular group held by the entity.

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-Publisher FASB
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-Topic 815
-SubTopic 10
-Section 50
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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