Allowance for Loan Losses and Credit Quality - Impaired Loans by Class (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Financing Receivable, Impaired [Line Items]
Recorded Investment	$ 194		$ 194		$ 1,790
Principal Balance	204		204		1,973
Related Allowance	23	$ 58	23	$ 58	46
With no allowance recorded, recorded investment	5,158		5,158		4,986
With no allowance recorded, principal balance	6,038		6,038		5,544
Total, recorded investment	5,352	7,177	5,352	7,177	6,776
Total, principal balance	6,242	8,064	6,242	8,064	7,517
Average Recorded Investment	5,941	7,286	6,219	6,398
Interest Income Recognized	81	49	119	123
Government guarantees on impaired loans	347	354	347	354	423
Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment	194		194		199
Principal Balance	204		204		209
Related Allowance	23	28	23	28	26
With no allowance recorded, recorded investment	1,345		1,345		1,551
With no allowance recorded, principal balance	1,832		1,832		2,043
Total, recorded investment	1,539	1,691	1,539	1,691	1,750
Total, principal balance	2,036	2,293	2,036	2,293	2,252
Average Recorded Investment	1,633	1,715	1,672	1,738
Interest Income Recognized	30	22	60	77
Construction real estate
Financing Receivable, Impaired [Line Items]
Related Allowance	0	0	0	0	0
With no allowance recorded, recorded investment	69		69		198
With no allowance recorded, principal balance	94		94		218
Total, recorded investment	69	208	69	208	198
Total, principal balance	94	229	94	229	218
Average Recorded Investment	131	209	153	209
Interest Income Recognized	24	1	25	2
Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment					1,591
Principal Balance					1,764
Related Allowance	0	30	0	30	20
With no allowance recorded, recorded investment	3,736		3,736		3,228
With no allowance recorded, principal balance	4,104		4,104		3,274
Total, recorded investment	3,736	5,266	3,736	5,266	4,819
Total, principal balance	4,104	5,528	4,104	5,528	5,038
Average Recorded Investment	4,169	5,271	4,386	4,321
Interest Income Recognized	27	25	34	38
Commercial
Financing Receivable, Impaired [Line Items]
Related Allowance	0	0	0	0	0
With no allowance recorded, recorded investment	8		8		9
With no allowance recorded, principal balance	8		8		9
Total, recorded investment	8	12	8	12	9
Total, principal balance	8	14	8	14	$ 9
Average Recorded Investment	8	91	8	130
Interest Income Recognized	$ 0	$ 1	$ 0	$ 6

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.

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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 https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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-Publisher FASB
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