Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 14,808	$ 14,438
Provision for Loan Losses	500	850
Recoveries	94	56
Loans Charged-off	(236)	(183)
Ending Balance	15,166	15,161
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,725	4,242
Provision for Loan Losses	(115)	105
Recoveries	2	4
Loans Charged-off	0	(5)
Ending Balance	3,612	4,346
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,452	6,342
Provision for Loan Losses	278	120
Recoveries	5	1
Loans Charged-off	(39)	0
Ending Balance	5,696	6,463
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,094	2,115
Provision for Loan Losses	267	414
Recoveries	0	0
Loans Charged-off	0	0
Ending Balance	4,361	2,529
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	283	383
Provision for Loan Losses	17	31
Recoveries	0	1
Loans Charged-off	(1)	(63)
Ending Balance	299	352
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	235	230
Provision for Loan Losses	118	27
Recoveries	60	45
Loans Charged-off	(169)	(72)
Ending Balance	244	230
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	329	414
Provision for Loan Losses	19	155
Recoveries	27	5
Loans Charged-off	(27)	(43)
Ending Balance	348	531
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	690	712
Provision for Loan Losses	(84)	(2)
Recoveries	0	0
Loans Charged-off	0	0
Ending Balance	$ 606	$ 710

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of expense related to estimated loss from loan and lease transactions.

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