Loans and Allowance (Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Impaired Financing Receivable With Related Allowance [Abstract]
Specific Allowance	$ 100	$ 100	$ 100
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	8,315	3,607	3,757
Unpaid principal balance, total	8,408	3,677	3,757
Average investment in impaired loans, total	4,148	3,408	5,222
Interest income recognized, total	32	40	109
Commercial Real Estate [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	6,324	878	665
Unpaid principal balance	6,377	878	665
Average investment in impaired loans	1,882	765	2,207
Interest income recognized		1	68
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	174	214	214
Unpaid principal balance	214	214	214
Specific Allowance	100	100	100
Average investment in impaired loans	206	214	416
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	6,498	1,092	879
Unpaid principal balance, total	6,591	1,092	879
Average investment in impaired loans, total	2,088	979	2,623
Interest income recognized, total		1	68
Commercial Segment [Member] \| Construction Loans [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	549	700	822
Unpaid principal balance	549	700	822
Average investment in impaired loans	633	762	874
Interest income recognized	27	33	40
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	549	700	822
Unpaid principal balance, total	549	700	822
Average investment in impaired loans, total	633	762	874
Interest income recognized, total	27	33	40
Commercial Segment [Member] \| Commercial and Industrial [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	131	272	187
Unpaid principal balance	131	342	187
Average investment in impaired loans	167	216	204
Interest income recognized	5	5	1
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	131	272	187
Unpaid principal balance, total	131	342	187
Average investment in impaired loans, total	167	216	204
Interest income recognized, total	5	5	1
Consumer [Member] \| First Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	1,137	1,543	1,869
Unpaid principal balance	1,137	1,543	1,869
Average investment in impaired loans	1,260	1,451	1,328
Interest income recognized		1
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	1,137	1,543	1,869
Unpaid principal balance, total	1,137	1,543	1,869
Average investment in impaired loans, total	$ 1,260	1,451	1,328
Interest income recognized, total		$ 1
Consumer [Member] \| Second Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Average investment in impaired loans			193
Impaired Financing Receivables Total [Abstract]
Average investment in impaired loans, total			$ 193

Impaired Financing Receivable With No 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.

+ 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=84173941&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=84173941&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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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+ References

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=84173941&loc=d3e5258-111524

Reference 2: 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=84173941&loc=d3e5212-111524

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