Loans (Schedule for Loans Individually Evaluated for Impairment) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
With No Related Allowance Recorded:
Unpaid Principal Balance	$ 1,233		$ 1,233		$ 1,719
Recorded Investment	751		751		1,107
Average Recorded Investment	1,770	$ 4,427	1,513	$ 2,549
Interest Income Recognized	47	9	56	51
Cash Basis Recognized	43	2	47	17
With An Allowance Recorded:
Unpaid Principal Balance	1,711		1,711		1,575
Recorded Investment	1,570		1,570		1,431
Allowance for Loan Losses Allocated	315		315		355
Average Recorded Investment	1,587	2,284	2,305	2,324
Interest Income Recognized	5	1	12	2
Cash Basis Recognized	0	0	7	0
Unpaid Principal Balance	2,944		2,944		3,294
Recorded Investment	2,321		2,321		2,538
Average Recorded Investment	3,357	6,711	3,818	4,873
Interest Income Recognized	52	10	68	53
Cash Basis Recognized	43	2	54	17
Receivables Acquired with Deteriorated Credit Quality
With No Related Allowance Recorded:
Unpaid Principal Balance	581		581		1,018
Recorded Investment	203		203		531
Average Recorded Investment	245	2,324	311	1,697
Interest Income Recognized	25	4	25	12
Cash Basis Recognized	25	1	25	2
With An Allowance Recorded:
Unpaid Principal Balance	844		844		910
Recorded Investment	705		705		768
Allowance for Loan Losses Allocated	55		55		100
Average Recorded Investment	712	0	721	0
Interest Income Recognized	4	0	11	0
Cash Basis Recognized	0	0	7	0
Commercial and Industrial Loans and Leases
With No Related Allowance Recorded:
Unpaid Principal Balance	196		196		85
Recorded Investment	139		139		29
Average Recorded Investment	150	185	83	133
Interest Income Recognized	2	3	2	25
Cash Basis Recognized	1	1	2	12
With An Allowance Recorded:
Unpaid Principal Balance	105		105		148
Recorded Investment	64		64		107
Allowance for Loan Losses Allocated	13		13		27
Average Recorded Investment	65	86	84	108
Interest Income Recognized	1	0	2	0
Cash Basis Recognized	0	0	1	0
Commercial Real Estate Loans
With No Related Allowance Recorded:
Unpaid Principal Balance	838		838		1,278
Recorded Investment	450		450		784
Average Recorded Investment	1,124	3,397	823	1,988
Interest Income Recognized	26	6	30	24
Cash Basis Recognized	26	1	29	4
With An Allowance Recorded:
Unpaid Principal Balance	800		800		839
Recorded Investment	791		791		827
Allowance for Loan Losses Allocated	184		184		280
Average Recorded Investment	795	2,198	1,609	2,216
Interest Income Recognized	4	1	10	2
Cash Basis Recognized	0	0	6	0
Agricultural Loans
With No Related Allowance Recorded:
Unpaid Principal Balance	199		199		356
Recorded Investment	162		162		294
Average Recorded Investment	496	845	607	428
Interest Income Recognized	19	0	24	2
Cash Basis Recognized	16	0	16	1
With An Allowance Recorded:
Unpaid Principal Balance	806		806		588
Recorded Investment	715		715		497
Allowance for Loan Losses Allocated	118		118		$ 48
Average Recorded Investment	727	0	612	0
Interest Income Recognized	0	0	0	0
Cash Basis Recognized	$ 0	$ 0	$ 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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-Section 50
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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
-Topic 310
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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