Loans, Allowance for Credit Losses - Loans, and Credit Quality - Schedule of Nonaccrual Loans by Portfolio Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 26,677	$ 26,625
Percent of total loans	0.40%	0.40%
% of Total	100.00%	100.00%
Retail & other
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 183	$ 172
% of Total	1.00%	1.00%
Commercial \| Commercial & industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 3,761	$ 4,046
% of Total	13.00%	15.00%
Commercial \| Owner-occupied CRE
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 4,721	$ 4,399
% of Total	18.00%	16.00%
Commercial \| Agricultural
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 12,418	$ 12,185
% of Total	47.00%	46.00%
Commercial real estate \| CRE investment
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 1,430	$ 1,453
% of Total	5.00%	5.00%
Commercial real estate \| Construction & land development
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 10	$ 161
% of Total	0.00%	1.00%
Residential \| Residential first mortgage
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 3,983	$ 4,059
% of Total	15.00%	15.00%
Residential \| Residential junior mortgage
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 171	$ 150
% of Total	1.00%	1.00%
Residential \| Residential construction
Financing Receivable, Past Due [Line Items]
Nonaccrual Loans	$ 0	$ 0
% of Total	0.00%	0.00%

Percentage of non accrual loan under each category.

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- Definition

Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-16

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- Definition

Percentage of nonaccrual financing receivable, excluding accrued interest, that is outstanding and past due. Excludes net investment in lease.

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-14

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 80
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479294/326-20-55-80

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