Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details)	12 Months Ended
Dec. 31, 2016 USD ($) loans	Dec. 31, 2015 USD ($) loans	Dec. 31, 2014 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans removed from TDR resignation \| loans	0	5
Recorded investment of loans removed from TDR resignation		$ 1,600,000
Recorded investment in Troubled Debt Restructurings	$ 18,168,000	19,081,000
TDR loans accruing interest as of period end	0	72,000
Acquired loans included in TDR	0	$ 137,000
Number of loans transferred to loans held-for-sale \| loans		1
Charge-off on loan transferred to held-for-sale	36,000	$ 864,000	$ 277,000
Gain (loss) on transfer of loans to held-for-sale		0
Commercial loans \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	2,207,000	4,698,000
Charge-off on loan transferred to held-for-sale	11,000	5,000	66,000
Commercial real estate loans \| Commercial real estate, owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	6,993,000	6,993,000
Charge-off on loan transferred to held-for-sale	20,000	0	0
Commercial real estate loans \| Commercial real estate, investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	2,256,000	514,000
Charge-off on loan transferred to held-for-sale	0	0	0
Commercial real estate loans \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	3,245,000	3,238,000
Loans reclassified to held-for-sale		1,500,000
Charge-off on loan transferred to held-for-sale	0	839,000	204,000
Residential loans \| Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	625,000	460,000
Charge-off on loan transferred to held-for-sale	0	0	0
Residential loans \| Other residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	1,965,000	2,010,000
Charge-off on loan transferred to held-for-sale	0	0	0
Consumer loans \| Installment and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	877,000	1,168,000
Charge-off on loan transferred to held-for-sale	$ 5,000	$ 20,000	$ 7,000

Reflects the carrying amount of trouble debt restructured loans on which interest is continuing to be accrued.

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Financing Receivable, Modifications, Removal From Troubled Debt Restructuring, Number Of Contracts

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Transfer Of Portfolio Loans And Leases To Held-for-sale, Number Of Loans

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Troubled Debt Restructuring, Loans Acquired

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

+ 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)(3)
-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 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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The amount of financing receivables reclassified to held for sale during the reporting period.

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