Allowance for Loan Credit Losses - Balance of allowance for loan losses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Individually evaluated for impairment	$ 0
Collectively evaluated for impairment		$ 20,208	$ 20,032
Total allowance	$ 0	20,208	20,032	$ 20,032
Individually evaluated for impairment		418	530
Collectively evaluated for impairment		1,785,030	1,721,401
Total loans		1,785,448	1,721,931
Unallocated
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment		638	583
Total allowance		638	583	632
Real Estate Loans \| Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment		13,205	13,435
Total allowance		13,205	13,435	13,091
Collectively evaluated for impairment		1,118,127	1,091,221
Total loans		1,118,127	1,091,221
Real Estate Loans \| Construction and land development
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment		2,860	2,921
Total allowance		2,860	2,921	2,824
Collectively evaluated for impairment		195,027	199,324
Total loans		195,027	199,324
Real Estate Loans \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment		3,044	2,583
Total allowance		3,044	2,583	2,769
Individually evaluated for impairment		418	530
Collectively evaluated for impairment		426,423	385,166
Total loans		426,841	385,696
Commercial - Non-Real Estate \| Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment		456	504
Total allowance		456	504	711
Collectively evaluated for impairment		44,924	45,105
Total loans		44,924	45,105
Consumer - Non-Real Estate \| Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Collectively evaluated for impairment		5	6
Total allowance		5	6	$ 5
Collectively evaluated for impairment		529	585
Total loans		$ 529	$ 585

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The balance of financing receivables that were collectively 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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