Loans and Allowance for Loan Losses - Loans Outstanding by Major Lending Classification (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	$ 1,848,784	$ 1,701,863	$ 1,415,896
Less: Allowance for loan losses	(21,747)	(24,460)	(29,030)	$ (32,353)
Net loans	1,827,037	1,677,403
Commercial and Industrial
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	386,233	318,791	265,818
Less: Allowance for loan losses	(5,309)	(5,135)	(6,600)	(6,756)
Construction
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	245,905	238,170	165,957
Less: Allowance for loan losses	(4,940)	(5,143)	(3,721)	(5,033)
Residential Real Estate \| 1-to-4 Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	294,924	290,704	266,641
Less: Allowance for loan losses	(3,197)	(4,176)	(6,364)	(7,211)
Residential Real Estate \| Residential Line of Credit
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	177,190	171,526	159,868
Less: Allowance for loan losses	(1,613)	(2,201)	(2,790)	(2,775)
Residential Real Estate \| Multi-Family Mortgage
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	44,977	59,510	52,238
Less: Allowance for loan losses	(504)	(311)	(184)	(342)
Commercial Real Estate \| Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	357,346	337,664	291,161
Less: Allowance for loan losses	(3,302)	(3,682)	(6,075)	(5,659)
Commercial Real Estate \| Non-Owner Occupied
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	267,902	207,871	151,980
Less: Allowance for loan losses	(2,019)	(2,622)	(2,641)	(3,438)
Consumer and Other
Financing Receivable Recorded Investment Past Due [Line Items]
Gross loans	74,307	77,627	62,233
Less: Allowance for loan losses	$ (863)	$ (1,190)	$ (655)	$ (1,139)

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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