Loans & Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	$ 2,578,120	$ 2,221,250
Less: Unearned Income	6,879	5,955
Total Loans & Leases	2,571,241	2,215,295
Less: Allowance for Credit Losses	55,266	50,342	$ 47,919
Loans & Leases, Net	2,515,975	2,164,953
Increase in loans and leases	356,900
Collateral on borrowing lines	753,600
Federal Home Loan Bank [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Collateral on borrowing lines	753,600
Maximum borrowing capacity	617,800
Federal Reserve Bank [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Collateral on borrowing lines	717,800
Maximum borrowing capacity	453,000
Bank of Rio Vista [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Increase in loans from acquisition	80,500
Commercial Real Estate [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	834,476	691,639
Total Loans & Leases	826,549	684,961
Less: Allowance for Credit Losses	11,609	10,922	11,110
Agricultural Real Estate [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	584,625	499,231
Total Loans & Leases	584,625	499,231
Less: Allowance for Credit Losses	14,092	12,085	9,450
Real Estate Construction [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	98,568	100,206
Total Loans & Leases	98,568	100,206
Less: Allowance for Credit Losses	1,249	1,846	3,223
Residential 1st Mortgages [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	259,736	260,751
Total Loans & Leases	259,736	260,751
Less: Allowance for Credit Losses	880	815	865
Home Equity Lines and Loans [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	40,789	34,525
Total Loans & Leases	40,789	34,525
Less: Allowance for Credit Losses	2,761	2,324	2,140
Agricultural [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	290,463	273,582
Total Loans & Leases	290,463	273,582
Less: Allowance for Credit Losses	8,242	8,159	7,381
Commercial [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	343,834	265,703
Total Loans & Leases	343,834	265,703
Less: Allowance for Credit Losses	11,656	9,197	8,515
Consumer & Other [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	19,412	6,656
Total Loans & Leases	19,412	6,656
Less: Allowance for Credit Losses	494	209	200
Leases [Member]
Loans and Leases Receivable, Net Amount [Abstract]
Total Gross Loans & Leases	106,217	88,957
Total Loans & Leases	107,265	89,680
Less: Allowance for Credit Losses	$ 4,022	$ 3,363	$ 3,586

The amount of loans receivable recognized as of the acquisition date.

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- Definition

Amount of increase (decrease) in loans and leases receivables.

+ References

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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.

+ References

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- Definition

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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- Definition

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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- Definition

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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