Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 16,243	$ 14,460	$ 15,823	$ 15,694
Provision for Loan Losses	250	1,220	925	1,570
Recoveries	144	114	290	214
Loans Charged-off	(398)	(157)	(799)	(1,841)
Ending Balance	16,239	15,637	16,239	15,637
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,317	3,603	2,953	4,735
Provision for Loan Losses	(303)	(44)	44	323
Recoveries	34	4	51	5
Loans Charged-off	(56)	0	(56)	(1,500)
Ending Balance	2,992	3,563	2,992	3,563
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,741	4,622	5,291	4,591
Provision for Loan Losses	104	335	669	360
Recoveries	14	5	19	11
Loans Charged-off	(18)	(4)	(138)	(4)
Ending Balance	5,841	4,958	5,841	4,958
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,453	4,825	5,776	4,894
Provision for Loan Losses	272	753	(51)	684
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	5,725	5,578	5,725	5,578
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	214	272	229	330
Provision for Loan Losses	54	86	39	42
Recoveries	0	8	0	10
Loans Charged-off	(10)	0	(10)	(16)
Ending Balance	258	366	258	366
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	483	316	420	298
Provision for Loan Losses	124	107	333	204
Recoveries	93	68	214	157
Loans Charged-off	(278)	(144)	(545)	(312)
Ending Balance	422	347	422	347
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	429	327	472	343
Provision for Loan Losses	(47)	19	(79)	1
Recoveries	3	29	6	31
Loans Charged-off	(36)	(9)	(50)	(9)
Ending Balance	349	366	349	366
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	606	495	682	503
Provision for Loan Losses	46	(36)	(30)	(44)
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	$ 652	$ 459	$ 652	$ 459

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

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-Publisher FASB
-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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