Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 15,694	$ 14,808	$ 14,438
Provision for Loan Losses	2,070	1,750	1,200
Recoveries	605	414	270
Loans Charged-off	(2,546)	(1,278)	(1,100)
Ending Balance	15,823	15,694	14,808
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,735	3,725	4,242
Provision for Loan Losses	(423)	1,147	(483)
Recoveries	141	14	32
Loans Charged-off	(1,500)	(151)	(66)
Ending Balance	2,953	4,735	3,725
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,591	5,452	6,342
Provision for Loan Losses	729	(689)	(846)
Recoveries	20	48	10
Loans Charged-off	(49)	(220)	(54)
Ending Balance	5,291	4,591	5,452
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,894	4,094	2,115
Provision for Loan Losses	862	840	2,000
Recoveries	20	9	1
Loans Charged-off	0	(49)	(22)
Ending Balance	5,776	4,894	4,094
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	330	283	383
Provision for Loan Losses	(52)	78	33
Recoveries	12	8	3
Loans Charged-off	(61)	(39)	(136)
Ending Balance	229	330	283
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	298	235	230
Provision for Loan Losses	608	517	273
Recoveries	375	272	208
Loans Charged-off	(861)	(726)	(476)
Ending Balance	420	298	235
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	343	329	414
Provision for Loan Losses	167	44	245
Recoveries	37	63	16
Loans Charged-off	(75)	(93)	(346)
Ending Balance	472	343	329
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	503	690	712
Provision for Loan Losses	179	(187)	(22)
Recoveries	0	0	0
Loans Charged-off	0	0	0
Ending Balance	$ 682	$ 503	$ 690

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

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-Name Accounting Standards Codification
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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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