Allowance for Loan Losses - Balance of allowance for loan losses (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	$ 20,032	$ 20,032
Total allowance	20,032	20,032	$ 19,706	$ 17,017
Individually evaluated for impairment	530	549
Collectively evaluated for impairment	1,721,401	1,665,005
Total loans	1,721,931	1,665,554
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	583	632
Total allowance	583	632	2,120	350
Real Estate Loans \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	2,583	2,769
Total allowance	2,583	2,769	2,518	2,430
Individually evaluated for impairment	530	549
Collectively evaluated for impairment	385,166	341,942
Total loans	385,696	342,491
Real Estate Loans \| Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	13,435	13,091
Total allowance	13,435	13,091
Collectively evaluated for impairment	1,091,221	968,442
Total loans	1,091,221	968,442
Real Estate Loans \| Construction and land development
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	2,921	2,824
Total allowance	2,921	2,824	1,835	2,617
Collectively evaluated for impairment	199,324	231,090
Total loans	199,324	231,090
Commercial - Non-Real Estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	504	711
Total allowance	504	711	715	1,007
Collectively evaluated for impairment	45,105	122,945
Total loans	45,105	122,945
Consumer - Non-Real Estate \| Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment	6	5
Total allowance	6	5	5	11
Collectively evaluated for impairment	585	586
Total loans	$ 585	$ 586
Commercial Real Estate \| Real Estate Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total allowance			$ 12,513	$ 10,602

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

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

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

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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.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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