Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 15,161	$ 15,169	$ 14,438	$ 14,929
Provision for Loan Losses	350	250	1,200	500
Recoveries	73	138	129	289
Loans Charged-off	(280)	(299)	(463)	(460)
Ending Balance	15,304	15,258	15,304	15,258
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,346	4,747	4,242	4,627
Provision for Loan Losses	(180)	(114)	(75)	(13)
Recoveries	24	26	28	67
Loans Charged-off	0	0	(5)	(22)
Ending Balance	4,190	4,659	4,190	4,659
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	6,463	7,229	6,342	7,273
Provision for Loan Losses	68	54	188	2
Recoveries	2	43	3	51
Loans Charged-off	0	(11)	0	(11)
Ending Balance	6,533	7,315	6,533	7,315
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,529	1,142	2,115	1,123
Provision for Loan Losses	175	81	589	100
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	2,704	1,223	2,704	1,223
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	352	318	383	246
Provision for Loan Losses	9	57	40	129
Recoveries	0	6	1	6
Loans Charged-off	(11)	(31)	(74)	(31)
Ending Balance	350	350	350	350
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	230	389	230	354
Provision for Loan Losses	66	5	93	40
Recoveries	43	54	88	154
Loans Charged-off	(97)	(66)	(169)	(166)
Ending Balance	242	382	242	382
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	531	673	414	622
Provision for Loan Losses	196	128	351	216
Recoveries	4	9	9	11
Loans Charged-off	(172)	(191)	(215)	(230)
Ending Balance	559	619	559	619
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	710	671	712	684
Provision for Loan Losses	16	39	14	26
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	$ 726	$ 710	$ 726	$ 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 of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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- Definition

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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