Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 15,823	$ 15,694	$ 14,808
Provision for Loan Losses	5,325	2,070	1,750
Recoveries	532	605	414
Loans Charged-off	(5,402)	(2,546)	(1,278)
Ending Balance	16,278	15,823	15,694
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,953	4,735	3,725
Provision for Loan Losses	5,600	(423)	1,147
Recoveries	56	141	14
Loans Charged-off	(3,810)	(1,500)	(151)
Ending Balance	4,799	2,953	4,735
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,291	4,591	5,452
Provision for Loan Losses	(308)	729	(689)
Recoveries	29	20	48
Loans Charged-off	(320)	(49)	(220)
Ending Balance	4,692	5,291	4,591
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,776	4,894	4,094
Provision for Loan Losses	(461)	862	840
Recoveries	0	20	9
Loans Charged-off	0	0	(49)
Ending Balance	5,315	5,776	4,894
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	229	330	283
Provision for Loan Losses	(27)	(52)	78
Recoveries	8	12	8
Loans Charged-off	(10)	(61)	(39)
Ending Balance	200	229	330
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	420	298	235
Provision for Loan Losses	727	608	517
Recoveries	432	375	272
Loans Charged-off	(1,145)	(861)	(726)
Ending Balance	434	420	298
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	472	343	329
Provision for Loan Losses	(29)	167	44
Recoveries	7	37	63
Loans Charged-off	(117)	(75)	(93)
Ending Balance	333	472	343
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	682	503	690
Provision for Loan Losses	(177)	179	(187)
Recoveries	0	0	0
Loans Charged-off	0	0	0
Ending Balance	$ 505	$ 682	$ 503

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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