Loans and Allowance for Loan Losses - Summary of Loans (Details) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment $ 1,124,046 $ 1,051,859    
Net deferred loan fees (4,169) (3,884)    
Loans held for investment 1,119,877 1,047,975    
Less allowance for loan losses (16,715) (15,557) $ (15,151) $ (14,390)
Total loans held for investment, net 1,103,162 1,032,418    
Real Estate Term        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 582,029 577,804    
Less allowance for loan losses (6,770) (6,783) (5,181) (7,268)
Construction and Land Development        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 240,120 179,664    
Less allowance for loan losses (5,449) (3,984) (4,425) (2,915)
Residential and Home Equity        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 72,959 71,169    
Less allowance for loan losses (617) (603) (671) (838)
Consumer and Other        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 15,678 14,945    
Less allowance for loan losses (161) (246) (266) (264)
Commercial Real Estate        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 822,149 757,468    
Less allowance for loan losses (12,219) (10,767)    
Commercial Real Estate | Real Estate Term        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 582,029 577,804    
Less allowance for loan losses (6,770) (6,783)    
Commercial Real Estate | Construction and Land Development        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 240,120 179,664    
Less allowance for loan losses (5,449) (3,984)    
Commercial and Industrial        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 213,260 208,277    
Less allowance for loan losses (3,718) (3,941) $ (4,608) $ (3,105)
Consumer        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 88,637 86,114    
Less allowance for loan losses (778) (849)    
Consumer | Residential and Home Equity        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 72,959 71,169    
Less allowance for loan losses (617) (603)    
Consumer | Consumer and Other        
Accounts Notes And Loans Receivable [Line Items]        
Gross loans held for investment 15,678 14,945    
Less allowance for loan losses $ (161) $ (246)