Allowance for Loan Losses and Credit Quality - Impaired Loans by Class (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 1,784		$ 1,790
Principal Balance	1,969		1,973
Related Allowance	44	$ 58	46
With no allowance recorded, recorded investment	4,746		4,986
With no allowance recorded, principal balance	5,372		5,544
Total, recorded investment	6,530	7,395	6,776
Total, principal balance	7,341	8,268	7,517
Average Recorded Investment	6,653	6,004
Interest Income Recognized	38	74
Government guarantees on impaired loans	420	489	423
Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	197		199
Principal Balance	207		209
Related Allowance	24	27	26
With no allowance recorded, recorded investment	1,531		1,551
With no allowance recorded, principal balance	2,028		2,043
Total, recorded investment	1,728	1,740	1,750
Total, principal balance	2,235	2,333	2,252
Average Recorded Investment	1,739	1,761
Interest Income Recognized	30	55
Construction real estate
Financing Receivable, Impaired [Line Items]
Related Allowance	0	0	0
With no allowance recorded, recorded investment	193		198
With no allowance recorded, principal balance	216		218
Total, recorded investment	193	210	198
Total, principal balance	216	230	218
Average Recorded Investment	195	210
Interest Income Recognized	1	1
Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	1,587		1,591
Principal Balance	1,762		1,764
Related Allowance	20	31	20
With no allowance recorded, recorded investment	3,014		3,228
With no allowance recorded, principal balance	3,120		3,274
Total, recorded investment	4,601	5,275	4,819
Total, principal balance	4,882	5,532	5,038
Average Recorded Investment	4,710	3,849
Interest Income Recognized	7	13
Commercial
Financing Receivable, Impaired [Line Items]
Related Allowance	0	0	0
With no allowance recorded, recorded investment	8		9
With no allowance recorded, principal balance	8		9
Total, recorded investment	8	170	9
Total, principal balance	8	173	$ 9
Average Recorded Investment	9	184
Interest Income Recognized	$ 0	$ 5

Amount of government guarantees related to impaired loans.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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