v3.8.0.1
Related Party Transactions - Additional Information (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2017
USD ($)
ExecutiveOfficer
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Related Party Transaction [Line Items]      
Gain on sale of loans $ 7,029 $ 7,812 $ 2,935
Directors, executive officers and affiliates      
Related Party Transaction [Line Items]      
Interest earned from loans to related parties 300 300 200
Deposits from related parties 5,100 2,900  
Interest paid 9 3 7
Assets under management 10,300    
Fees amount received 100 100  
Chief Executive Officer      
Related Party Transaction [Line Items]      
Deposits from related parties 70,400    
Interest paid 300   700
Average amount of borrowings     16,600
Purchase of loans 121,900 41,400  
Gain on sale of loans 1,100 600  
Loans serviced for other financial institution 155,300    
Interest on loan 200 200 200
Loans and leases, participating sub debt offering 15,000    
Gain on loans and leases, participating sub debt offering $ 100    
FFB      
Related Party Transaction [Line Items]      
Number of executive officers | ExecutiveOfficer 2    
Minority interests of executive officers $ 200    
FFA      
Related Party Transaction [Line Items]      
Assets under management 260,000 236,000  
Subadvisory fees earned by FFA $ 400 $ 400 $ 400