Loans and Allowance for Loan Losses - Troubled Debt Restructuring by Class (Details) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) loans	Mar. 31, 2015 USD ($) loans	Dec. 31, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans removed from TDR designation \| loans	0	1
Loans removed from TDR designation, recorded investment	$ 108
Recorded investment in Troubled Debt Restructurings	19,724		$ 19,081
TDR loans accruing interest as of period end	19,700		19,000
TDR loans acquired	621		137
Charge-off to allowance for loan losses	9	$ 8
Commercial loans \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	3,825		4,698
Charge-off to allowance for loan losses	9	2
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		6,993
Charge-off to allowance for loan losses	0	0
Commercial real estate loans \| Commercial real estate, investor
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	2,052		514
Charge-off to allowance for loan losses	0	0
Commercial real estate loans \| Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	3,238		3,238
Charge-off to allowance for loan losses	0	0
Residential loans \| Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	458		460
Charge-off to allowance for loan losses	0	0
Residential loans \| Other residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	1,997		2,010
Charge-off to allowance for loan losses	0	0
Consumer loans \| Installment and other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment in Troubled Debt Restructurings	1,161		$ 1,168
Charge-off to allowance for loan losses	$ 0	$ 6

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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=49124121&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

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