Allowance for Loan Losses and Credit Quality - Allocation of the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	$ 44	$ 46
Collectively evaluated for impairment	8,292	8,290
Total allocated	8,336	8,336	$ 8,429	$ 8,271
Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	24	26
Collectively evaluated for impairment	2,200	2,042
Total allocated	2,224	2,068	1,996	1,776
Construction real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	843	837
Total allocated	843	837	881	763
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	20	20
Collectively evaluated for impairment	3,977	4,102
Total allocated	3,997	4,122	4,133	4,199
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	289	275
Total allocated	289	275	443	458
Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	10	11
Total allocated	10	11	13	15
Municipal
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	88	86
Total allocated	88	86	199	214
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	885	937
Total allocated	$ 885	$ 937	$ 764	$ 846

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

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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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