Loans and Allowance for Loan Losses (Details 10) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of activity related to our allowance for loan losses
Balance, beginning of period	$ 14,855	$ 13,629	$ 11,752
Provision	2,000	2,300	3,200
Loan charge-offs	(1,638)	(1,648)	(1,508)
Loan recoveries	306	574	185
Net loan charge-offs	(1,332)	(1,074)	(1,323)
Balance, end of period	15,523	14,855	13,629
Commercial [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	10,039	9,672	8,216
Provision	920	987
Loan charge-offs	(1,227)	(1,178)
Loan recoveries	205	558
Net loan charge-offs	(1,022)	(620)
Balance, end of period	9,937	10,039	9,672
Consumer [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period	4,816	3,957	3,536
Provision	1,080	1,313
Loan charge-offs	(411)	(470)
Loan recoveries	101	16
Net loan charge-offs	(310)	(454)
Balance, end of period	5,586	4,816	3,957
Unallocated [Member]
Summary of activity related to our allowance for loan losses
Balance, beginning of period
Provision
Loan charge-offs
Loan recoveries
Net loan charge-offs
Balance, end of period

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

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

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from recoveries of amounts previously written off or reestablishment of reserves that had previously been utilized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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