Allowance for Loan Losses - Activity by Class (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 16,201	$ 17,034	$ 15,521	$ 16,253	$ 16,253
Charge offs	260	158	619	637	748
Recoveries	46	106	185	316	391
Provision (credit)	400	525	1,300	1,575	(375)
Ending balance	16,387	17,507	16,387	17,507	15,521
Ending balance specifically evaluated for impairment	420	682	420	682	576
Ending balance collectively evaluated for impairment	15,967	16,825	15,967	16,825	14,945
Ending balance	1,857,975	1,617,212	1,857,975	1,617,212	1,647,649
Ending balance specifically evaluated for impairment	6,355	14,549	6,355	14,549	12,052
Ending balance collectively evaluated for impairment	1,851,620	1,602,663	1,851,620	1,602,663	1,635,597
Commercial \| Real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,480	6,088	5,367	5,178	5,178
Charge offs	0	66	0	71	106
Recoveries	(1)	0	16	95	95
Provision (credit)	96	477	192	1,297	200
Ending balance	5,575	6,499	5,575	6,499	5,367
Ending balance specifically evaluated for impairment	0	138	0	138	42
Ending balance collectively evaluated for impairment	5,575	6,361	5,575	6,361	5,325
Ending balance	638,708	550,077	638,708	550,077	576,198
Ending balance specifically evaluated for impairment	1,295	2,800	1,295	2,800	1,428
Ending balance collectively evaluated for impairment	637,413	547,277	637,413	547,277	574,770
Commercial \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,151	750	746	662	662
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	(30)	129	375	217	84
Ending balance	1,121	879	1,121	879	746
Ending balance specifically evaluated for impairment	6	18	6	18	16
Ending balance collectively evaluated for impairment	1,115	861	1,115	861	730
Ending balance	129,036	73,302	129,036	73,302	79,365
Ending balance specifically evaluated for impairment	686	705	686	705	689
Ending balance collectively evaluated for impairment	128,350	72,597	128,350	72,597	78,676
Commercial \| Other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,948	3,757	2,830	3,438	3,438
Charge offs	229	0	272	286	288
Recoveries	9	81	11	83	84
Provision (credit)	286	(111)	445	492	(404)
Ending balance	3,014	3,727	3,014	3,727	2,830
Ending balance specifically evaluated for impairment	315	397	315	397	381
Ending balance collectively evaluated for impairment	2,699	3,330	2,699	3,330	2,449
Ending balance	310,110	288,121	310,110	288,121	264,570
Ending balance specifically evaluated for impairment	951	1,755	951	1,755	1,303
Ending balance collectively evaluated for impairment	309,159	286,366	309,159	286,366	263,267
Municipal
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	157	187	157	171	171
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	3	2	3	18	(14)
Ending balance	160	189	160	189	157
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	160	189	160	189	157
Ending balance	48,702	40,616	48,702	40,616	48,362
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	48,702	40,616	48,702	40,616	48,362
Residential \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	191	160	148	102	102
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	(23)	(18)	20	40	46
Ending balance	168	142	168	142	148
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	168	142	168	142	148
Ending balance	41,631	29,358	41,631	29,358	31,763
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	41,631	29,358	41,631	29,358	31,763
Residential \| Term
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,592	2,896	2,733	2,579	2,579
Charge offs	0	0	0	41	42
Recoveries	16	3	27	12	66
Provision (credit)	(61)	(138)	(213)	211	130
Ending balance	2,547	2,761	2,547	2,761	2,733
Ending balance specifically evaluated for impairment	99	129	99	129	137
Ending balance collectively evaluated for impairment	2,448	2,632	2,448	2,632	2,596
Ending balance	595,031	537,811	595,031	537,811	550,783
Ending balance specifically evaluated for impairment	3,176	8,782	3,176	8,782	8,173
Ending balance collectively evaluated for impairment	591,855	529,029	591,855	529,029	542,610
Home equity line of credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	966	959	925	1,211	1,211
Charge offs	0	0	29	0	0
Recoveries	2	12	3	60	61
Provision (credit)	25	(15)	94	(315)	(347)
Ending balance	993	956	993	956	925
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	993	956	993	956	925
Ending balance	73,938	74,594	73,938	74,594	73,632
Ending balance specifically evaluated for impairment	247	503	247	503	457
Ending balance collectively evaluated for impairment	73,691	74,091	73,691	74,091	73,175
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	866	892	833	778	778
Charge offs	31	92	318	239	312
Recoveries	20	10	128	66	85
Provision (credit)	17	57	229	262	282
Ending balance	872	867	872	867	833
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	872	867	872	867	833
Ending balance	20,819	23,333	20,819	23,333	22,976
Ending balance specifically evaluated for impairment	0	4	0	4	2
Ending balance collectively evaluated for impairment	20,819	23,329	20,819	23,329	22,974
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,850	1,345	1,782	2,134	2,134
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	87	142	155	(647)	(352)
Ending balance	1,937	1,487	1,937	1,487	1,782
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	1,937	1,487	1,937	1,487	1,782
Ending balance	0	0	0	0	0
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	$ 0	$ 0	$ 0	$ 0	$ 0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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

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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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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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