Loans and Allowance (Impaired Loans) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Impaired Financing Receivable With Related Allowance [Abstract]
Specific Allowance	$ 127	$ 100	$ 127	$ 100	$ 100
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	7,460	2,802	7,460	2,802	8,315
Unpaid principal balance, total	7,460	2,802	7,460	2,802	8,408
Average investment in impaired loans, total	7,338	2,787	7,752	3,107	4,148
Interest income recognized, total	74	8	327	25	32
Commercial Real Estate [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	5,607	703	5,607	703	6,324
Unpaid principal balance	5,607	703	5,607	703	6,377
Average investment in impaired loans	5,609	704	5,962	772	1,882
Interest income recognized	70		312
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance		214		214	174
Unpaid principal balance		214		214	214
Specific Allowance		100		100	100
Average investment in impaired loans		214		214	206
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	5,607	917	5,607	917	6,498
Unpaid principal balance, total	5,607	917	5,607	917	6,591
Average investment in impaired loans, total	5,609	918	5,962	986	2,088
Interest income recognized, total	70		312
Commercial Segment [Member] \| Construction Loans [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	371	607	371	607	549
Unpaid principal balance	371	607	371	607	549
Average investment in impaired loans	373	623	459	653	633
Interest income recognized	4	7	13	21	27
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	371	607	371	607	549
Unpaid principal balance, total	371	607	371	607	549
Average investment in impaired loans, total	373	623	459	653	633
Interest income recognized, total	4	7	13	21	27
Commercial Segment [Member] \| Commercial and Industrial [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	48	138	48	138	131
Unpaid principal balance	48	138	48	138	131
Average investment in impaired loans	49	141	97	177	167
Interest income recognized		1	2	4	5
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	48	138	48	138	131
Unpaid principal balance, total	48	138	48	138	131
Average investment in impaired loans, total	49	141	97	177	167
Interest income recognized, total		1	2	4	5
Consumer [Member] \| First Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	844	1,140	844	1,140	1,137
Unpaid principal balance	844	1,140	844	1,140	1,137
Average investment in impaired loans	844	1,105	918	1,291	1,260
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	336		336
Unpaid principal balance	336		336
Specific Allowance	40		40
Average investment in impaired loans	336		252
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	1,180	1,140	1,180	1,140	1,137
Unpaid principal balance, total	1,180	1,140	1,180	1,140	1,137
Average investment in impaired loans, total	1,180	$ 1,105	1,170	$ 1,291	$ 1,260
Consumer [Member] \| Boat/RVs [Member]
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	254		254
Unpaid principal balance	254		254
Specific Allowance	87		87
Average investment in impaired loans	127		64
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	254		254
Unpaid principal balance, total	254		254
Average investment in impaired loans, total	$ 127		$ 64

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