v3.8.0.1
Loan Sales And Mortgage Servicing Rights - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Loan Sales And Mortgage Servicing Rights [Line Items]      
Gain on sale of loans $ 545 $ 300  
Mortgage servicing rights created from loan sales 317 113  
FFB      
Loan Sales And Mortgage Servicing Rights [Line Items]      
Gain on sale of loans   500 $ 7,000
Sale of multifamily loans through securitization   52,000 453,000
Mortgage servicing rights recorded   $ 300  
Mortgage servicing rights created from loan sales 4,900   4,800
Loans serviced for others 793,000   745,000
Servicing fees earned on loans $ 200   $ 700