Loans - Collateral-dependent Loans by Class (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 3,978,919	$ 3,977,900
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	572,666	589,541
Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,148,808	2,121,835
Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	400,733	423,803
Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	73,496	71,988
Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	312,859	299,685
Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	88,008	87,853
Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	21,113	20,351
Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	361,236	362,844
Total
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	20,371	19,733
Total | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	6,294	5,605
Total | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8,937	8,553
Total | Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	4,111	4,393
Total | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Total | Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	421	420
Total | Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	9	9
Total | Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Total | Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	599	753
Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	17,321	16,741
Real Estate | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	4,269	3,668
Real Estate | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	8,937	8,553
Real Estate | Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,086	3,338
Real Estate | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Real Estate | Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	421	420
Real Estate | Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	9	9
Real Estate | Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Real Estate | Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	599	753
Equipment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,232	1,104
Equipment | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	207	49
Equipment | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Equipment | Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,025	1,055
Equipment | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Equipment | Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Equipment | Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Equipment | Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Equipment | Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Accounts Receivable | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0
Accounts Receivable | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable | Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable | Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable | Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable | Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Accounts Receivable | Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,818	1,888
Other | Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,818	1,888
Other | Commercial Real Estate Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Agricultural Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Home Equity Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Credit Cards
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	0	0
Other | Residential Mortgage Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 0	$ 0