Loans - Summary of Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	$ 24,523	$ 26,748
Recorded Investment	23,322	20,891
Related Allowance	2,601	2,420
Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	48,501	36,335
Recorded Investment	42,041	30,586
Commercial \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	11,877	17,337
Recorded Investment	11,824	14,412
Related Allowance	839	993
Commercial \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	14,839	7,267
Recorded Investment	12,509	5,888
SBA \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	6,634	4,671
Recorded Investment	5,664	1,956
Related Allowance	294	156
SBA \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,815	9,135
Recorded Investment	1,133	8,045
Construction \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Related Allowance	0	0
Construction \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	5,995	7,875
Recorded Investment	4,520	6,394
Indirect automobile \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Related Allowance	0	0
Indirect automobile \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	0	0
Recorded Investment	0	0
Installment \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	343	283
Recorded Investment	290	235
Related Allowance	219	235
Installment \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	1,445	1,445
Recorded Investment	163	163
Residential mortgage \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	4,838	3,178
Recorded Investment	4,799	3,117
Related Allowance	616	703
Residential mortgage \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	21,955	9,464
Recorded Investment	21,398	9,347
Home equity lines of credit \| Impaired Loans with Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	831	1,279
Recorded Investment	745	1,171
Related Allowance	633	333
Home equity lines of credit \| Impaired Loans with No Allowance
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance	2,452	1,149
Recorded Investment	$ 2,318	$ 749

Impaired financing receivable amortized cost for amortized cost.

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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

Amount of allowance for credit losses related to recorded investment.

+ 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without 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 (a)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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