Loans - Changes in allowance for loan losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Summary of the activity in the allowance for loan losses by portfolio segment
Beginning balance	$ 2,433	$ 2,424	$ 2,430	$ 2,811
Provision for loan losses	93	0	93	0
Loans charged off		(1)	(3)	(393)
Recoveries of loans previously charged off	4	3	10	8
Ending balance	2,530	2,426	2,530	2,426
Commercial
Summary of the activity in the allowance for loan losses by portfolio segment
Beginning balance	1,375	1,590	1,516	1,834
Provision for loan losses	204	(31)	63	116
Loans charged off		(1)	0	(393)
Recoveries of loans previously charged off		1		2
Ending balance	1,579	1,559	1,579	1,559
Residential real estate and consumer
Summary of the activity in the allowance for loan losses by portfolio segment
Beginning balance	1,058	834	914	977
Provision for loan losses	(111)	31	30	(116)
Loans charged off			(3)	0
Recoveries of loans previously charged off	4	2	10	6
Ending balance	$ 951	$ 867	$ 951	$ 867

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ 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
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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Amount of expense related to estimated loss from loan and lease transactions.

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