Loans and Allowance (Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance			$ 7,760
Unpaid principal balance			8,720
Average investment in impaired loans			7,264
Interest income recognized			214
Impaired Financing Receivable With Related Allowance [Abstract]
Specific Allowance	$ 100	$ 100
Interest income recognized		225
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	3,757	6,700
Unpaid principal balance, total	3,757	6,700
Average investment in impaired loans, total	5,222	7,578
Interest income recognized, total	109
Commercial Real Estate [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	665	3,608	4,933
Unpaid principal balance	665	3,608	4,933
Average investment in impaired loans	2,207	4,115	3,776
Interest income recognized	68	172	161
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	214	676
Unpaid principal balance	214	676
Specific Allowance	100	100
Average investment in impaired loans	416	793
Interest income recognized		20
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	879	4,284
Unpaid principal balance, total	879	4,284
Average investment in impaired loans, total	2,623	4,908
Interest income recognized, total	68	192
Commercial Segment [Member] \| Construction Loans [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	822	595	931
Unpaid principal balance	822	595	1,860
Average investment in impaired loans	874	735	1,323
Interest income recognized	40	31	30
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	822	595
Unpaid principal balance, total	822	595
Average investment in impaired loans, total	874	735
Interest income recognized, total	40	31
Commercial Segment [Member] \| Commercial and Industrial [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	187	214	758
Unpaid principal balance	187	214	789
Average investment in impaired loans	204	423	923
Interest income recognized	1	2	12
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	187	214
Unpaid principal balance, total	187	214
Average investment in impaired loans, total	204	423
Interest income recognized, total	1	2
Consumer [Member] \| First Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	1,869	1,126	1,138
Unpaid principal balance	1,869	1,126	1,138
Average investment in impaired loans	1,328	1,131	1,142
Interest income recognized			8
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	1,869	1,126
Unpaid principal balance, total	1,869	1,126
Average investment in impaired loans, total	1,328	1,131
Consumer [Member] \| Second Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance		481
Unpaid principal balance		481
Average investment in impaired loans	193		100
Interest income recognized			$ 3
Impaired Financing Receivable With Related Allowance [Abstract]
Average investment in impaired loans		381
Impaired Financing Receivables Total [Abstract]
Recorded balance, total		481
Unpaid principal balance, total		481
Average investment in impaired loans, total	$ 193	$ 381

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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.

+ References

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)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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