Loans and Allowance (Impaired Loans) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Impaired Financing Receivable With Related Allowance [Abstract]
Specific Allowance	$ 40	$ 100	$ 100
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	8,009	3,246	8,315
Unpaid principal balance, total	8,157	3,246	8,408
Average investment in impaired loans, total	8,162	3,426	4,148
Interest income recognized, total	175	9	32
Commercial Real Estate [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	6,133	801	6,324
Unpaid principal balance	6,281	801	6,377
Average investment in impaired loans	6,315	839	1,882
Interest income recognized	169
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance		214	174
Unpaid principal balance		214	214
Specific Allowance		100	100
Average investment in impaired loans		214	206
Interest income recognized		1
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	6,133	1,015	6,498
Unpaid principal balance, total	6,281	1,015	6,591
Average investment in impaired loans, total	6,315	1,053	2,088
Interest income recognized, total	169	1
Commercial Segment [Member] \| Construction Loans [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	539	668	549
Unpaid principal balance	539	668	549
Average investment in impaired loans	544	684	633
Interest income recognized	5	7	27
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	539	668	549
Unpaid principal balance, total	539	668	549
Average investment in impaired loans, total	544	684	633
Interest income recognized, total	5	7	27
Commercial Segment [Member] \| Commercial and Industrial [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	158	152	131
Unpaid principal balance	158	152	131
Average investment in impaired loans	145	212	167
Interest income recognized	1		5
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	158	152	131
Unpaid principal balance, total	158	152	131
Average investment in impaired loans, total	145	212	167
Interest income recognized, total	1		5
Consumer [Member] \| First Mortgage [Member]
Impaired Financing Receivable With No Related Allowance [Abstract]
Recorded balance	844	1,411	1,137
Unpaid principal balance	844	1,411	1,137
Average investment in impaired loans	990	1,477	1,260
Interest income recognized		1
Impaired Financing Receivable With Related Allowance [Abstract]
Recorded balance	335
Unpaid principal balance	335
Specific Allowance	40
Average investment in impaired loans	168
Impaired Financing Receivables Total [Abstract]
Recorded balance, total	1,179	1,411	1,137
Unpaid principal balance, total	1,179	1,411	1,137
Average investment in impaired loans, total	$ 1,158	1,477	$ 1,260
Interest income recognized, total		$ 1

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

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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=84173941&loc=d3e5258-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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