Loans - Composition of Net Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 827,607	$ 787,050
Allowance for loan losses	(8,336)	(8,336)	$ (8,429)	$ (8,271)
Net deferred loan costs	1,007	705
Net loans	820,278	779,419
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	282,662	246,827
Allowance for loan losses	(2,224)	(2,068)	(1,996)	(1,776)
Construction real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	68,730	65,149
Allowance for loan losses	(843)	(837)	(881)	(763)
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	348,378	344,816
Allowance for loan losses	(3,997)	(4,122)	(4,133)	(4,199)
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	44,808	49,788
Allowance for loan losses	(289)	(275)	(443)	(458)
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	2,241	2,376
Allowance for loan losses	(10)	(11)	(13)	(15)
Municipal
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	80,788	78,094
Allowance for loan losses	$ (88)	$ (86)	$ (199)	$ (214)

Financing Receivable, Excluding Accrued Interest, Deferred Loan (Fees) Costs

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- Definition

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.

+ References

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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- Definition

Amount excluding accrued interest, after allowance for credit loss, of financing receivable.

+ References

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- Definition

Amount excluding accrued interest, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3B
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447

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