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Loans and Allowance for Credit Losses - Loans by Type as Percentage of Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 1,418,590	$ 1,410,653
Allowance for loan losses (Note 3)	$ 16,037	$ 15,685	$ 15,065	$ 7,619
Percentage of allowance for credit losses	1.13%	1.11%
Loans, net	$ 1,402,553	$ 1,394,968
Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 41,950	$ 49,210
Percentage of loans	3.00%	3.50%
Percentage of increase decrease of loans	(14.80%)
Allowance for loan losses (Note 3)	$ 97	$ 94	135	144
Commercial and Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 231,222	$ 229,915
Percentage of loans	16.30%	16.30%
Percentage of increase decrease of loans	0.60%
Allowance for loan losses (Note 3)	$ 2,243	$ 2,216	3,020	1,361
Commercial Real Estate Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 794,705	$ 786,921
Percentage of loans	56.00%	55.80%
Percentage of increase decrease of loans	1.00%
Allowance for loan losses (Note 3)	$ 9,167	$ 8,820	7,837	4,822
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 34,268	$ 36,541
Percentage of loans	2.40%	2.60%
Percentage of increase decrease of loans	(6.20%)
Allowance for loan losses (Note 3)	$ 918	$ 823	913	310
Construction Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 17,890	$ 20,936
Percentage of loans	1.30%	1.50%
Percentage of increase decrease of loans	(14.50%)
Allowance for loan losses (Note 3)	$ 49	$ 58	73	63
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 268,523	$ 267,730
Percentage of loans	18.90%	19.00%
Percentage of increase decrease of loans	0.30%
Allowance for loan losses (Note 3)	$ 3,513	$ 3,644	$ 3,087	$ 906
Loans To Other Financial Institutions [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans (Note 3)	$ 30,032	$ 19,400
Percentage of loans	2.10%	1.40%
Percentage of increase decrease of loans	54.80%
Allowance for loan losses (Note 3)	$ 50	$ 30

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Percentage of allowance for credit losses.

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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.

+ References

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-SubTopic 30
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
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-Topic 310
-Publisher FASB
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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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-Section 45
-Paragraph 2
-Publisher FASB
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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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