Allowance for Loan Losses - Activity by Class (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	$ 16,594	$ 11,858	$ 16,253	$ 11,639	$ 11,639
Charge offs	200	162	479	417	1,661
Recoveries	115	64	210	138	225
Provision (credit)	525	2,350	1,050	2,750	6,050
Ending balance	17,034	14,110	17,034	14,110	16,253
Ending balance specifically evaluated for impairment	707	917	707	917	462
Ending balance collectively evaluated for impairment	16,327	13,193	16,327	13,193	15,791
Ending balance	1,588,264	1,451,623	1,588,264	1,451,623	1,476,761
Ending balance specifically evaluated for impairment	15,578	20,013	15,578	20,013	16,039
Ending balance collectively evaluated for impairment	1,572,686	1,431,610	1,572,686	1,431,610	1,460,722
Commercial \| Real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	5,741	3,862	5,178	3,742	3,742
Charge offs	0	0	5	0	1,088
Recoveries	30	0	95	0	0
Provision (credit)	317	649	820	769	2,524
Ending balance	6,088	4,511	6,088	4,511	5,178
Ending balance specifically evaluated for impairment	167	199	167	199	112
Ending balance collectively evaluated for impairment	5,921	4,312	5,921	4,312	5,066
Ending balance	527,415	397,155	527,415	397,155	442,121
Ending balance specifically evaluated for impairment	3,074	5,749	3,074	5,749	3,029
Ending balance collectively evaluated for impairment	524,341	391,406	524,341	391,406	439,092
Commercial \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	649	424	662	365	365
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	101	100	88	159	297
Ending balance	750	524	750	524	662
Ending balance specifically evaluated for impairment	19	20	19	20	18
Ending balance collectively evaluated for impairment	731	504	731	504	644
Ending balance	65,794	47,169	65,794	47,169	56,565
Ending balance specifically evaluated for impairment	787	934	787	934	770
Ending balance collectively evaluated for impairment	65,007	46,235	65,007	46,235	55,795
Commercial \| Other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	4,080	2,427	3,438	3,329	3,329
Charge offs	144	17	286	17	27
Recoveries	2	0	2	20	37
Provision (credit)	(181)	1,279	603	357	99
Ending balance	3,757	3,689	3,757	3,689	3,438
Ending balance specifically evaluated for impairment	403	132	403	132	169
Ending balance collectively evaluated for impairment	3,354	3,557	3,354	3,557	3,269
Ending balance	298,747	327,967	298,747	327,967	285,015
Ending balance specifically evaluated for impairment	1,989	853	1,989	853	1,779
Ending balance collectively evaluated for impairment	296,758	327,114	296,758	327,114	283,236
Municipal
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	185	29	171	27	27
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	2	81	16	83	144
Ending balance	187	110	187	110	171
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	187	110	187	110	171
Ending balance	41,079	49,644	41,079	49,644	43,783
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	41,079	49,644	41,079	49,644	43,783
Residential \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	131	32	102	25	25
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	29	32	58	39	77
Ending balance	160	64	160	64	102
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	160	64	160	64	102
Ending balance	29,818	14,707	29,818	14,707	21,600
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	29,818	14,707	29,818	14,707	21,600
Residential \| Term
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	2,962	1,226	2,579	1,024	1,024
Charge offs	12	44	41	46	66
Recoveries	3	16	9	26	34
Provision (credit)	(57)	1,063	349	1,257	1,587
Ending balance	2,896	2,261	2,896	2,261	2,579
Ending balance specifically evaluated for impairment	118	269	118	269	163
Ending balance collectively evaluated for impairment	2,778	1,992	2,778	1,992	2,416
Ending balance	523,344	499,693	523,344	499,693	522,070
Ending balance specifically evaluated for impairment	9,126	10,311	9,126	10,311	9,414
Ending balance collectively evaluated for impairment	514,218	489,382	514,218	489,382	512,656
Home equity line of credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	947	1,012	1,211	1,078	1,078
Charge offs	0	0	0	153	153
Recoveries	47	18	48	19	22
Provision (credit)	(35)	254	(300)	340	264
Ending balance	959	1,284	959	1,284	1,211
Ending balance specifically evaluated for impairment	0	292	0	292	0
Ending balance collectively evaluated for impairment	959	992	959	992	1,211
Ending balance	77,709	87,019	77,709	87,019	79,750
Ending balance specifically evaluated for impairment	596	2,161	596	2,161	1,039
Ending balance collectively evaluated for impairment	77,113	84,858	77,113	84,858	78,711
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	872	725	778	867	867
Charge offs	44	101	147	201	327
Recoveries	33	30	56	73	132
Provision (credit)	31	4	205	(81)	106
Ending balance	892	658	892	658	778
Ending balance specifically evaluated for impairment	0	5	0	5	0
Ending balance collectively evaluated for impairment	892	653	892	653	778
Ending balance	24,358	28,269	24,358	28,269	25,857
Ending balance specifically evaluated for impairment	6	5	6	5	8
Ending balance collectively evaluated for impairment	24,352	28,264	24,352	28,264	25,849
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance	1,027	2,121	2,134	1,182	1,182
Charge offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Provision (credit)	318	(1,112)	(789)	(173)	952
Ending balance	1,345	1,009	1,345	1,009	2,134
Ending balance specifically evaluated for impairment	0	0	0	0	0
Ending balance collectively evaluated for impairment	1,345	1,009	1,345	1,009	2,134
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

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

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

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

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

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Amount, before allowance for credit loss, of financing receivable.

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