Loans and Allowance for Loan Losses (Details 9) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	$ 15,762	$ 15,523
Provision for loan losses	300	500
Loan charge-offs	(41)	(293)
Loan recoveries	30	122
Net loan charge-offs	(11)	(171)
Balance, end of period	$ 16,051	$ 15,852
Net charge-offs to average loans (annualized)	0.00%	0.05%
Allowance for loan losses to gross loans	0.93%	1.09%
Allowance for loan losses to nonperforming loans	265.35%	217.92%
Commercial [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	$ 10,768
Balance, end of period	11,037
Commercial [Member] \| Owner occupied RE [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	2,726	$ 2,534
Provision for loan losses	57	146
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	2,783	2,680
Commercial [Member] \| Non-owner occupied RE [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,811	3,230
Provision for loan losses	74	135
Loan charge-offs
Loan recoveries	1	1
Net loan charge-offs	1	1
Balance, end of period	3,886	3,366
Commercial [Member] \| Business [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,616	3,848
Provision for loan losses	171	(294)
Loan charge-offs		(119)
Loan recoveries	9	118
Net loan charge-offs	9	(1)
Balance, end of period	3,796	3,553
Commercial [Member] \| Construction [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	615	325
Provision for loan losses	(43)	90
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	572	415
Consumer [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	4,994
Balance, end of period	5,014
Consumer [Member] \| Other [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	290	281
Provision for loan losses	29	31
Loan charge-offs	(41)	(34)
Loan recoveries	3	2
Net loan charge-offs	(38)	(32)
Balance, end of period	281	280
Consumer [Member] \| Real Estate [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	3,081	3,495
Provision for loan losses	(56)	(105)
Loan charge-offs
Loan recoveries	16	1
Net loan charge-offs	16	1
Balance, end of period	3,041	3,391
Consumer [Member] \| Home equity [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	1,348	1,600
Provision for loan losses	61	451
Loan charge-offs		(140)
Loan recoveries	1
Net loan charge-offs	1	(140)
Balance, end of period	1,410	1,911
Consumer [Member] \| Construction [Member]
Financing Receivable, Allowance For Credit Losses [Roll Forward]
Balance, beginning of period	275	210
Provision for loan losses	7	46
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period	$ 282	$ 256

Allowance for loan and lease losses write offs net of recoveries.

No definition available.

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- Definition

Allowance for loan losses as a percentage of gross loans.

+ References

No definition available.

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- Definition

Allowance for credit losses as a percentage of nonperforming loans.

+ References

No definition available.

+ Details

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- Definition

Net loan charge offs annualized as a percentage of average total loans.

+ References

No definition available.

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from recovery of amount previously written off or reestablishment of reserve previously utilized.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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