Loans (Schedule of Allowance for Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 15,258	$ 15,550	$ 14,929	$ 14,584
Provision for Loan Losses	(500)	0	0	550
Recoveries	90	121	379	1,065
Loans Charged-off	(78)	(79)	(538)	(607)
Ending Balance	14,770	15,592	14,770	15,592
Commercial and Industrial Loans and Leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	4,659	5,661	4,627	3,983
Provision for Loan Losses	(337)	(563)	(350)	1,124
Recoveries	16	19	83	97
Loans Charged-off	(5)	0	(27)	(87)
Ending Balance	4,333	5,117	4,333	5,117
Commercial Real Estate Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,315	7,199	7,273	8,335
Provision for Loan Losses	(568)	206	(566)	(1,546)
Recoveries	30	55	81	785
Loans Charged-off	0	(6)	(11)	(120)
Ending Balance	6,777	7,454	6,777	7,454
Agricultural Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,223	1,016	1,123	946
Provision for Loan Losses	754	156	854	226
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	1,977	1,172	1,977	1,172
Home Equity Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	350	418	246	239
Provision for Loan Losses	(41)	(33)	88	148
Recoveries	2	0	8	42
Loans Charged-off	(2)	(7)	(33)	(51)
Ending Balance	309	378	309	378
Consumer Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	382	326	354	188
Provision for Loan Losses	(105)	77	(65)	296
Recoveries	39	41	193	127
Loans Charged-off	(71)	(65)	(237)	(232)
Ending Balance	245	379	245	379
Residential Mortgage Loans
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	619	435	622	281
Provision for Loan Losses	(172)	(33)	44	229
Recoveries	3	6	14	14
Loans Charged-off	0	(1)	(230)	(117)
Ending Balance	450	407	450	407
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	710	495	684	612
Provision for Loan Losses	(31)	190	(5)	73
Recoveries	0	0	0	0
Loans Charged-off	0	0	0	0
Ending Balance	$ 679	$ 685	$ 679	$ 685

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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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 SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

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Amount of expense related to estimated loss from loan and lease transactions.

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