Note 1 - Summary of Significant Accounting Policies (Details Textual)
$ in Thousands
 2 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Apr. 01, 2015
USD ($)
Jan. 01, 2015
USD ($)
shares
Oct. 01, 2014
USD ($)
Mar. 31, 2017
USD ($)
Mar. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Jun. 30, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2016
USD ($)
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Dec. 31, 2012
USD ($)
Number of Service Branches           25     25 25      
Number of Limited-hour Retirement Community Offices           8     8 8      
Number of Limited-service Branches           1     1 1      
Number of Wealth Offices           5     5 5      
Cash Reserve Deposit Required and Made           $ 10,400   $ 11,700 $ 10,400 $ 10,400 $ 11,700    
Delinquency Period after Which the Accrual of Interest Is Generally Discontinued                   90 days      
Delinquency Period after Which a Lease Is Charged Off                   120 days      
Period after Which Nonaccrual Loans and Leases May Be Returned to Accrual Status                   180 days      
Federal Home Loan Bank Stock           17,305   12,942 17,305 $ 17,305 12,942    
Federal Reserve Bank Stock           6,900     6,900 6,900      
Derivative, Notional Amount           15,000     $ 15,000 15,000      
Debt Instrument, Face Amount                         $ 15,000
Other than Temporary Impairment Losses, Investments                   0 0 $ 0  
Recognition of Tax Benefit in Consolidated Statements of Income [Member]                          
Current Period Reclassification Adjustment                   565      
Forward Contracts [Member]                          
Derivative, Notional Amount                         15,000
Federal Home Loan Bank [Member]                          
Debt Instrument, Face Amount                         $ 15,000
Royal Bancshares of Pennsylvania, Inc. [Member] | Scenario, Forecast [Member]                          
Business Combination, Consideration Transferred       $ 127,700 $ 127,700                
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans       602,000 602,000                
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deposit Liabilities       630,000 630,000                
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables       $ 602,000 $ 602,000                
Robert J. McAllister Agency, Inc. ("RJM") [Member]                          
Business Combination, Consideration Transferred $ 1,000                        
Payments to Acquire Businesses, Gross $ 500                        
Business Combination, Payment of Contingent Consideration Installment             $ 85            
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High, Each Installment             $ 100            
Business Combination, Number of Remaining Contingent Consideration Installments                 4        
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High, Each Remaining Installment           100     $ 100 100      
Continental Bank Holdings, Inc. ("CBH") [Member]                          
Business Combination, Consideration Transferred   $ 125,059                      
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deposit Liabilities   $ 481,674                      
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares   3,878,383                      
Business Combination, Consideration Transferred, Equity Interest, Fair Value of Stock Options   $ 2,343                      
Business Combination, Consideration Transferred, Equity Interest Cash Out of Certain Warrants   1,323                      
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables   424,737                      
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities   $ 181,838                      
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Number of Branches   10                      
Powers Craft Parker and Beard (PCPB) [Member]                          
Business Combination, Consideration Transferred     $ 7,024                    
Payments to Acquire Businesses, Gross     5,399                    
Business Combination, Payment of Contingent Consideration Installment           $ 542   $ 542          
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High, Each Installment     542                    
Business Combination, Number of Remaining Contingent Consideration Installments           1   2          
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High, Each Remaining Installment           $ 542   $ 542 542 542 542    
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities     $ 302                    
Business Combination, Number of Consideration Installments     3                    
Business Combination, Remaining Contingent Consideration Installment           $ 542   $ 1,100 $ 542 $ 542 $ 1,100