Loans (Schedule for Loans Individually Evaluated for Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
With No Related Allowance Recorded:
Unpaid Principal Balance	$ 1,678		$ 1,719
Recorded Investment	1,522		1,107
Average Recorded Investment	1,257	$ 2,299
Interest Income Recognized	9	42
Cash Basis Recognized	4	15
With An Allowance Recorded:
Unpaid Principal Balance	3,214		1,575
Recorded Investment	3,038		1,431
Allowance for Loan Losses Allocated	644		355
Average Recorded Investment	3,023	2,364
Interest Income Recognized	7	1
Cash Basis Recognized	7	0
Unpaid Principal Balance	4,892		3,294
Recorded Investment	4,560		2,538
Average Recorded Investment	4,280	4,663
Interest Income Recognized	16	43
Cash Basis Recognized	11	15
Receivables Acquired with Deteriorated Credit Quality
With No Related Allowance Recorded:
Unpaid Principal Balance	599		1,018
Recorded Investment	584		531
Average Recorded Investment	209	782
Interest Income Recognized	0	8
Cash Basis Recognized	0	1
With An Allowance Recorded:
Unpaid Principal Balance	1,053		910
Recorded Investment	1,052		768
Allowance for Loan Losses Allocated	111		100
Average Recorded Investment	1,007	0
Interest Income Recognized	7	0
Cash Basis Recognized	7	0
Commercial and Industrial Loans and Leases
With No Related Allowance Recorded:
Unpaid Principal Balance	57		85
Recorded Investment	57		29
Average Recorded Investment	16	827
Interest Income Recognized	0	23
Cash Basis Recognized	0	11
With An Allowance Recorded:
Unpaid Principal Balance	140		148
Recorded Investment	137		107
Allowance for Loan Losses Allocated	26		27
Average Recorded Investment	103	129
Interest Income Recognized	1	0
Cash Basis Recognized	1	0
Commercial Real Estate Loans
With No Related Allowance Recorded:
Unpaid Principal Balance	921		1,278
Recorded Investment	808		784
Average Recorded Investment	522	1,213
Interest Income Recognized	4	18
Cash Basis Recognized	4	3
With An Allowance Recorded:
Unpaid Principal Balance	2,487		839
Recorded Investment	2,314		827
Allowance for Loan Losses Allocated	570		280
Average Recorded Investment	2,423	2,235
Interest Income Recognized	6	1
Cash Basis Recognized	6	0
Agricultural Loans
With No Related Allowance Recorded:
Unpaid Principal Balance	700		356
Recorded Investment	657		294
Average Recorded Investment	719	259
Interest Income Recognized	5	1
Cash Basis Recognized	0	1
With An Allowance Recorded:
Unpaid Principal Balance	587		588
Recorded Investment	587		497
Allowance for Loan Losses Allocated	48		$ 48
Average Recorded Investment	497	0
Interest Income Recognized	0	0
Cash Basis Recognized	$ 0	$ 0

Impaired Financing Receivable, with No Related Allowance [Abstract]

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Impaired Financing Receivable, with Related Allowance [Abstract]

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
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-Publisher FASB
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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of allowance for credit losses related to recorded investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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