v3.19.1
Loans and Allowance for Loan Losses - Loans Held-For-Sale (Details) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Transfer of loans to held-for-sale   $ 0  
Sales of loans held-for-investment $ 0 0 $ 0
Purchases of loans held-for-investment   0 0
Loans held-for-sale 5,781,000 5,297,000  
Commercial and Industrial | Commercial property      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Transfer of loans to held-for-sale 2,100,000    
Commercial and Industrial | SBA commercial term      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Loans held-for-sale 300,000 1,170,000  
Real Estate | Residential property      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Transfer of loans to held-for-sale 6,000,000   $ 22,100,000
Purchases of loans held-for-investment 0    
Loans held-for-sale 0 270,000  
Real Estate | SBA loan pool securities      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Loans held-for-sale $ 5,481,000 $ 3,857,000