Loans - Summary of Recorded Investment in Impaired Portfolio Loans by Category (Details) - Non-Covered Loans	3 Months Ended
	Mar. 31, 2017 USD ($) loan	Dec. 31, 2016 USD ($)
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Modifications, Number of Contracts | loan	0
Non-accrual	$ 12,015,000	$ 13,060,000
Restructured	2,331,000	2,331,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0
Total Recorded Investment	14,346,000	15,391,000
Commercial and industrial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	9,692,000	10,046,000
Restructured	2,311,000	2,311,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0.000	0.000
Total Recorded Investment	12,003,000	12,357,000
Commercial - investor owned
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	282,000	435,000
Restructured	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0
Total Recorded Investment	282,000	435,000
Commercial - owner occupied
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	0	231,000
Restructured	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0
Total Recorded Investment	0	231,000
Construction and land development
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	1,979,000	2,286,000
Restructured	20,000	20,000
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0
Total Recorded Investment	1,999,000	2,306,000
Residential real estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	62,000	62,000
Restructured	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0
Total Recorded Investment	62,000	62,000
Consumer and other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Non-accrual	0	0
Restructured	0	0
Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance	0	0
Total Recorded Investment	$ 0	$ 0