Loans & Leases and Allowance for Credit Losses, Loan & Lease Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	$ 2,676,626	$ 2,680,011	$ 2,570,581
Less: Unearned Income	6,517	6,984	6,613
Total Loans & Leases	2,670,109	2,673,027	2,563,968
Less: Allowance for Credit Losses	54,824	55,012	54,907	$ 55,266
Loans & Leases, Net	2,615,285	2,618,015	2,509,061
Commercial Real Estate [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	868,736	846,486	823,028
Total Loans & Leases	861,311	838,570	815,366
Less: Allowance for Credit Losses	11,122	11,053	11,400	11,609
Agricultural Real Estate [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	594,154	625,767	603,601
Total Loans & Leases	594,154	625,767	603,601
Less: Allowance for Credit Losses	14,469	15,128	14,493	14,092
Real Estate Construction [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	126,956	115,644	99,837
Total Loans & Leases	126,956	115,644	99,837
Less: Allowance for Credit Losses	1,927	1,949	1,207	1,249
Residential 1st Mortgages [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	256,732	255,253	258,359
Total Loans & Leases	256,732	255,253	258,359
Less: Allowance for Credit Losses	1,037	855	863	880
Home Equity Lines and Loans [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	40,747	39,270	40,072
Total Loans & Leases	40,747	39,270	40,072
Less: Allowance for Credit Losses	2,783	2,675	2,738	2,761
Agricultural [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	264,771	292,904	257,004
Total Loans & Leases	264,771	292,904	257,004
Less: Allowance for Credit Losses	6,959	8,076	7,448	8,242
Commercial [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	404,329	384,795	364,439
Total Loans & Leases	404,329	384,795	364,439
Less: Allowance for Credit Losses	12,214	11,466	11,933	11,656
Consumer & Other [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	14,839	15,422	18,418
Total Loans & Leases	14,839	15,422	18,418
Less: Allowance for Credit Losses	382	456	467	494
Leases [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	105,362	104,470	105,823
Total Loans & Leases	106,270	105,402	106,872
Less: Allowance for Credit Losses	$ 3,188	$ 3,162	$ 4,008	$ 4,022

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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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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