Loans Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 17,216	$ 16,287	$ 17,012	$ 16,038
Charge-offs	(305)	(200)	(575)	(417)
Recoveries	109	42	225	107
Provision	422	669	780	1,070
Allowance for Loan Losses, Ending Balance	17,442	16,798	17,442	16,798
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	146	250	146	250	$ 0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	17,296	16,548	17,296	16,548	17,012
Ending Loan Balance - Individually Evaluated for Impairment	2,859	4,275	2,859	4,275	2,079
Ending Loan Balance - Collectively Evaluated for Impairment	1,875,773	1,668,215	1,875,773	1,668,215	1,751,189
Commercial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	939	1,437	1,017	1,827
Charge-offs	(23)	(11)	(39)	(52)
Recoveries	5	2	12	15
Provision	4	(300)	(65)	(662)
Allowance for Loan Losses, Ending Balance	925	1,128	925	1,128
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	112	0	112	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	813	1,128	813	1,128	1,017
Ending Loan Balance - Individually Evaluated for Impairment	503	0	503	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	125,756	106,651	125,756	106,651	105,155
Commercial Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	5,449	4,950	5,677	4,520
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	(466)	866	(694)	1,296
Allowance for Loan Losses, Ending Balance	4,983	5,816	4,983	5,816
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	250	0	250	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	4,983	5,566	4,983	5,566	5,677
Ending Loan Balance - Individually Evaluated for Impairment	1,178	3,542	1,178	3,542	890
Ending Loan Balance - Collectively Evaluated for Impairment	440,631	414,070	440,631	414,070	430,756
Consumer Loans Financing
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	6,702	5,912	6,120	5,554
Charge-offs	(277)	(189)	(530)	(349)
Recoveries	104	40	213	92
Provision	776	(21)	1,502	445
Allowance for Loan Losses, Ending Balance	7,305	5,742	7,305	5,742
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	7,305	5,742	7,305	5,742	6,120
Ending Loan Balance - Individually Evaluated for Impairment	88	93	88	93	91
Ending Loan Balance - Collectively Evaluated for Impairment	578,666	508,445	578,666	508,445	537,270
Residential
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	4,126	3,798	4,198	3,790
Charge-offs	(5)	0	(6)	(16)
Recoveries	0	0	0	0
Provision	108	228	37	252
Allowance for Loan Losses, Ending Balance	4,229	4,026	4,229	4,026
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	34	0	34	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	4,195	4,026	4,195	4,026	4,198
Ending Loan Balance - Individually Evaluated for Impairment	1,090	640	1,090	640	1,098
Ending Loan Balance - Collectively Evaluated for Impairment	730,720	639,049	730,720	639,049	678,008
Unallocated
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	0	190	0	347
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	0	(104)	0	(261)
Allowance for Loan Losses, Ending Balance	0	86	0	86
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0	0	0	0	0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	0	86	0	86	0
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	$ 0	$ 0	$ 0	$ 0	$ 0

No definition available.

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossAdditionalInformationAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRecovery
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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.

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesWriteOffs
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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=66008989&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=66902209&loc=d3e3602-108585

+ Details

Name:	us-gaap_ProvisionForLoanLeaseAndOtherLosses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_UnallocatedFinancingReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: