Allowance for Loan Losses - Balance in Allowance for Loan Losses and Recorded Investment in Loans by Impairment (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Financing Receivable Impaired [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 1,413
Allowance for Loan Losses, Collectively Evaluated for Impairment	16,087	$ 15,400
Total Allowance for Loan Losses	17,500	15,400
Unaccreted Credit Component Other Loans	257	432
Loans, Individually Evaluated for Impairment	14,350	8,994
Loans, Collectively Evaluated for Impairment	3,233,693	2,539,649
Total loans	3,249,860	2,552,016
Unaccreted Credit Component Other Loans	34,864	59,037
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable Impaired [Line Items]
Loans, Purchased Impaired	1,817	3,373
Residential Properties
Financing Receivable Impaired [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	9,320	6,669
Total Allowance for Loan Losses	9,320	6,669
Unaccreted Credit Component Other Loans	84	128
Loans, Individually Evaluated for Impairment		6,093
Loans, Collectively Evaluated for Impairment	2,400,539	1,774,796
Total loans	2,400,539	1,780,889
Unaccreted Credit Component Other Loans	9,043	12,373
Commercial Real Estate
Financing Receivable Impaired [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	3,566	2,983
Total Allowance for Loan Losses	3,566	2,983
Unaccreted Credit Component Other Loans	78	136
Loans, Individually Evaluated for Impairment	3,603	2,148
Loans, Collectively Evaluated for Impairment	525,822	474,634
Total loans	529,590	476,959
Unaccreted Credit Component Other Loans	10,290	24,796
Commercial Real Estate \| Receivables Acquired with Deteriorated Credit Quality
Financing Receivable Impaired [Line Items]
Loans, Purchased Impaired	165	177
Land and Construction
Financing Receivable Impaired [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	353	233
Total Allowance for Loan Losses	353	233
Unaccreted Credit Component Other Loans		2
Loans, Collectively Evaluated for Impairment	31,304	24,100
Total loans	31,304	24,100
Unaccreted Credit Component Other Loans		437
Commercial and Industrial Loans
Financing Receivable Impaired [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	1,413
Allowance for Loan Losses, Collectively Evaluated for Impairment	2,560	5,227
Total Allowance for Loan Losses	3,973	5,227
Unaccreted Credit Component Other Loans	89	147
Loans, Individually Evaluated for Impairment	10,747	753
Loans, Collectively Evaluated for Impairment	247,559	233,992
Total loans	259,958	237,941
Unaccreted Credit Component Other Loans	14,771	20,165
Commercial and Industrial Loans \| Receivables Acquired with Deteriorated Credit Quality
Financing Receivable Impaired [Line Items]
Loans, Purchased Impaired	1,652	3,196
Consumer Loans
Financing Receivable Impaired [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	288	288
Total Allowance for Loan Losses	288	288
Unaccreted Credit Component Other Loans	6	19
Loans, Collectively Evaluated for Impairment	28,469	32,127
Total loans	28,469	32,127
Unaccreted Credit Component Other Loans	$ 760	$ 1,266

Allowance for loan losses in unaccreted credit component other loans.

No definition available.

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- Definition

Loans and lease receivable in unaccreted credit component other loan.

+ References

No definition available.

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- Definition

Loans and leases receivable allowance impaired.

+ References

No definition available.

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- Definition

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

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

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

+ References

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- Definition

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

+ 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 (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ 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 (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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