Loans and Allowance (Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Impaired Financing Receivable With Related Allowance [Abstract]
Specific Allowance	$ 127	$ 100	$ 100
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	7,660	8,315	3,607
Unpaid principal balance, total	7,660	8,408	3,677
Average investment in impaired loans, total	7,733	4,148	3,408
Interest income recognized, total	396	32	40
Commercial Real Estate [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	5,542	6,324	878
Unpaid principal balance	5,542	6,377	878
Average investment in impaired loans	5,878	1,882	765
Interest income recognized	377		1
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance		174	214
Unpaid principal balance		214	214
Specific Allowance		100	100
Average investment in impaired loans		206	214
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	5,542	6,498	1,092
Unpaid principal balance, total	5,542	6,591	1,092
Average investment in impaired loans, total	5,878	2,088	979
Interest income recognized, total	377		1
Commercial Segment [Member] \| Construction Loans [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	642	549	700
Unpaid principal balance	642	549	700
Average investment in impaired loans	496	633	762
Interest income recognized	17	27	33
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	642	549	700
Unpaid principal balance, total	642	549	700
Average investment in impaired loans, total	496	633	762
Interest income recognized, total	17	27	33
Commercial Segment [Member] \| Commercial and Industrial [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	44	131	272
Unpaid principal balance	44	131	342
Average investment in impaired loans	86	167	216
Interest income recognized	2	5	5
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	44	131	272
Unpaid principal balance, total	44	131	342
Average investment in impaired loans, total	86	167	216
Interest income recognized, total	2	5	5
Consumer [Member] \| First Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	844	1,137	1,543
Unpaid principal balance	844	1,137	1,543
Average investment in impaired loans	903	1,260	1,451
Interest income recognized			1
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	337
Unpaid principal balance	337
Specific Allowance	40
Average investment in impaired loans	269
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	1,181	1,137	1,543
Unpaid principal balance, total	1,181	1,137	1,543
Average investment in impaired loans, total	1,172	$ 1,260	1,451
Interest income recognized, total			$ 1
Consumer [Member] \| Boat/RVs [Member]
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	251
Unpaid principal balance	251
Specific Allowance	87
Average investment in impaired loans	101
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	251
Unpaid principal balance, total	251
Average investment in impaired loans, total	$ 101

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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