Loans & Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	$ 2,680,011	$ 2,578,120
Less: Unearned Income	6,984	6,879
Total Loans & Leases	2,673,027	2,571,241
Less: Allowance for Credit Losses	55,012	55,266	$ 50,342
Loans & Leases, Net	2,618,015	2,515,975
Collateral on borrowing lines	793,500
Federal Home Loan Bank [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Collateral on borrowing lines	793,500
Maximum borrowing capacity	668,400
Federal Reserve Bank [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Collateral on borrowing lines	696,500
Maximum borrowing capacity	441,300
Commercial Real Estate [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	846,486	834,476
Total Loans & Leases	838,570	826,549
Less: Allowance for Credit Losses	11,053	11,609	10,922
Agricultural Real Estate [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	625,767	584,625
Total Loans & Leases	625,767	584,625
Less: Allowance for Credit Losses	15,128	14,092	12,085
Real Estate Construction [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	115,644	98,568
Total Loans & Leases	115,644	98,568
Less: Allowance for Credit Losses	1,949	1,249	1,846
Residential 1st Mortgages [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	255,253	259,736
Total Loans & Leases	255,253	259,736
Less: Allowance for Credit Losses	855	880	815
Home Equity Lines and Loans [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	39,270	40,789
Total Loans & Leases	39,270	40,789
Less: Allowance for Credit Losses	2,675	2,761	2,324
Agricultural [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	292,904	290,463
Total Loans & Leases	292,904	290,463
Less: Allowance for Credit Losses	8,076	8,242	8,159
Commercial [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	384,795	343,834
Total Loans & Leases	384,795	343,834
Less: Allowance for Credit Losses	11,466	11,656	9,197
Consumer & Other [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	15,422	19,412
Total Loans & Leases	15,422	19,412
Less: Allowance for Credit Losses	456	494	209
Leases [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	104,470	106,217
Total Loans & Leases	105,402	107,265
Less: Allowance for Credit Losses	$ 3,162	$ 4,022	$ 3,363

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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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Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts 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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Amount before allowance and after 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.

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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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