Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 15,823	$ 15,694
Provision for Loan Losses	675	350
Recoveries	146	100
Loans Charged-off	(401)	(1,684)
Ending Balance	16,243	14,460
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,953	4,735
Provision for Loan Losses	347	367
Recoveries	17	1
Loans Charged-off	0	(1,500)
Ending Balance	3,317	3,603
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,291	4,591
Provision for Loan Losses	565	25
Recoveries	5	6
Loans Charged-off	(120)	0
Ending Balance	5,741	4,622
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,776	4,894
Provision for Loan Losses	(323)	(69)
Recoveries	0	0
Loans Charged-off	0	0
Ending Balance	5,453	4,825
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	229	330
Provision for Loan Losses	(15)	(44)
Recoveries	0	2
Loans Charged-off	0	(16)
Ending Balance	214	272
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	420	298
Provision for Loan Losses	209	97
Recoveries	121	89
Loans Charged-off	(267)	(168)
Ending Balance	483	316
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	472	343
Provision for Loan Losses	(32)	(18)
Recoveries	3	2
Loans Charged-off	(14)	0
Ending Balance	429	327
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	682	503
Provision for Loan Losses	(76)	(8)
Recoveries	0	0
Loans Charged-off	0	0
Ending Balance	$ 606	$ 495

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount, after recoveries, of loans and leases that have been written-off.

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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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Amount of expense related to estimated loss from loan and lease transactions.

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