Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 16,239	$ 15,637	$ 15,823	$ 15,694
Provision for Loan Losses	2,800	500	3,725	2,070
Recoveries	114	182	404	396
Loans Charged-off	(3,284)	(268)	(4,083)	(2,109)
Ending Balance	15,869	16,051	15,869	16,051
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,992	3,563	2,953	4,735
Provision for Loan Losses	4,468	(444)	4,512	(121)
Recoveries	2	69	53	74
Loans Charged-off	(2,859)	0	(2,915)	(1,500)
Ending Balance	4,603	3,188	4,603	3,188
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,841	4,958	5,291	4,591
Provision for Loan Losses	(1,410)	138	(741)	498
Recoveries	5	7	24	18
Loans Charged-off	(136)	(9)	(274)	(13)
Ending Balance	4,300	5,094	4,300	5,094
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,725	5,578	5,776	4,894
Provision for Loan Losses	(373)	618	(424)	1,302
Recoveries	0	20	0	20
Loans Charged-off	0	0	0	0
Ending Balance	5,352	6,216	5,352	6,216
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	258	366	229	330
Provision for Loan Losses	(72)	(80)	(33)	(38)
Recoveries	8	1	8	11
Loans Charged-off	0	(10)	(10)	(26)
Ending Balance	194	277	194	277
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	422	347	420	298
Provision for Loan Losses	174	195	507	399
Recoveries	99	82	313	239
Loans Charged-off	(277)	(238)	(822)	(550)
Ending Balance	418	386	418	386
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	349	366	472	343
Provision for Loan Losses	25	67	(54)	68
Recoveries	0	3	6	34
Loans Charged-off	(12)	(11)	(62)	(20)
Ending Balance	362	425	362	425
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	652	459	682	503
Provision for Loan Losses	(12)	6	(42)	(38)
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	$ 640	$ 465	$ 640	$ 465

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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