Quarterly report pursuant to Section 13 or 15(d)

Loans - Additional Information (Details)

v3.21.1
Loans - Additional Information (Details) - USD ($)
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Accounts Notes And Loans Receivable [Line Items]      
Pledged loans, collateral for FHLB advances $ 971,500,000   $ 927,300,000
Pledged loans, collateral under PPPLF 100,100,000   149,800,000
Servicing loans sold 410,800,000   400,300,000
Realized gains on servicing loans sold $ 99,000    
Percentage of loan balance purchased 95.00%    
Unpaid principal balances of loans serviced $ 10,500,000    
Amount outstanding [1] 2,430,594,000   2,388,532,000
Unfunded commitments to related parties 314,459,000   312,683,000
Executive Officers and Directors      
Accounts Notes And Loans Receivable [Line Items]      
Unfunded commitments to related parties 2,000,000.0   1,800
Loan Held for Investment and Long-term Borrowings      
Accounts Notes And Loans Receivable [Line Items]      
Secured borrowings 4,000,000.0   4,000,000.0
Consumer Mortgage Loans      
Accounts Notes And Loans Receivable [Line Items]      
Recorded mortgage loans in process of foreclosure 0   0
SBA Loans      
Accounts Notes And Loans Receivable [Line Items]      
Unpaid principal balances of loans serviced 186,400,000   $ 193,300,000
Paycheck protection program loans under CARES Act $ 366,500,000    
PPP loan interest rate 1.00%    
Deferred origination fees $ 6,700,000    
Weighted average life of debt 2 years 3 months 18 days    
Amount outstanding $ 100,100,000    
Interest rate 0.35%    
SBA Loans | Minimum      
Accounts Notes And Loans Receivable [Line Items]      
Paycheck protection program loans contractual term 2 years    
SBA Loans | Maximum      
Accounts Notes And Loans Receivable [Line Items]      
Paycheck protection program loans contractual term 5 years    
SBA Loans | Third Party      
Accounts Notes And Loans Receivable [Line Items]      
Servicing loans sold $ 2,000,000.0 $ 5,600,000  
Realized gains on servicing loans sold $ 155,000 $ 464,000  
[1] Organic loans balance includes $(11.9) million and $(8.2) million of deferred fees, cost, premium and discount as of March 31, 2021 and December 31, 2020, respectively.