Annual report pursuant to Section 13 and 15(d)

Note 1 - Summary of Significant Accounting Policies (Details Textual)

v3.20.4
Note 1 - Summary of Significant Accounting Policies (Details Textual)
 12 Months Ended
Dec. 31, 2020
USD ($)
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Jan. 01, 2020
USD ($)
Jan. 01, 2019
USD ($)
Dec. 31, 2017
USD ($)
Number of Reporting Units 1          
Unrecognized Tax Benefits Threshold Percentage   50.00%        
Advertising Expense $ 338,000 $ 581,000 $ 557,000      
Retained Earnings (Accumulated Deficit), Ending Balance 748,224,000 616,611,000        
Loans and Leases Receivable, Allowance, Ending Balance 87,942,000 76,584,000 68,600,000     $ 59,406,000
Deferred Income Tax Assets, Net, Total 31,072,000 25,566,000        
Loans and Leases Receivable, Gross, Total 8,465,688,000 7,261,451,000        
Commercial Real Estate Portfolio Segment [Member]            
Loans and Leases Receivable, Allowance, Ending Balance 36,370,000 43,666,000 39,016,000      
Loans and Leases Receivable, Gross, Total 3,295,900,000 2,696,210,000        
Real Estate Portfolio Segment[Member]            
Loans and Leases Receivable, Gross, Total 4,511,304,000 3,979,060,000        
Real Estate Portfolio Segment[Member] | Construction Loans [Member]            
Loans and Leases Receivable, Allowance, Ending Balance 16,057,000 2,768,000 $ 3,522,000      
Loans and Leases Receivable, Gross, Total $ 593,614,000 521,392,000        
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]            
Retained Earnings (Accumulated Deficit), Ending Balance       $ 1,100,000    
Loans and Leases Receivable, Allowance, Ending Balance       (2,000,000.0)    
Off-Balance Sheet, Credit Loss, Liability, Ending Balance       500,000    
Deferred Income Tax Assets, Net, Total       (400,000)    
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Commercial Real Estate Portfolio Segment [Member]            
Loans and Leases Receivable, Gross, Total       (8,200,000)    
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Real Estate Portfolio Segment[Member] | Construction Loans [Member]            
Loans and Leases Receivable, Gross, Total       $ 6,200,000    
Accounting Standards Update 2016-02 [Member]            
Operating Lease, Right-of-Use Asset         $ 15,300,000  
Operating Lease, Liability, Total         $ 15,300,000  
Interest Rate Cap [Member]            
Derivative, Term of Contract (Year) 3 years          
Derivative, Notional Amount $ 300,000,000          
Interest Rate Cap [Member] | Not Designated as Hedging Instrument [Member]            
Derivative, Term of Contract (Year) 3 years          
Derivative, Notional Amount $ 300,000,000          
Interest Rate Cap [Member] | Not Designated as Hedging Instrument [Member] | London Interbank Offered Rate (LIBOR) [Member]            
Derivative, Variable Interest Rate 0.50%          
Metro Bancshares, Inc [Member]            
Finite-Lived Intangible Assets, Remaining Amortization Period (Year) 7 years          
Goodwill, Ending Balance $ 13,600,000          
Minimum [Member]            
Property, Plant and Equipment, Useful Life (Year) 3 years          
Lessee, Operating Lease, Renewal Term (Year) 1 year          
Maximum [Member]            
Property, Plant and Equipment, Useful Life (Year) 39 years 6 months          
Lessee, Operating Lease, Renewal Term (Year) 5 years          
Federal Reserve Bank [Member]            
Cash Reserve Deposit Required and Made $ 0 $ 33,900,000