Note 5 - Loans and Leases - Roll-forward of Allowance for Loan and Leases Losses by Loan Category (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Balance       $ 15,857       $ 14,586 $ 15,857 $ 14,586  
Charge-offs                 (3,287) (3,454)  
Recoveries                 590 329  
Provision for loan and lease losses $ 1,059 $ 1,412 $ 445 1,410 $ 1,777 $ 1,200 $ 850 569 4,326 4,396 $ 884
Balance 17,486       15,857       17,486 15,857 14,586
Real Estate Portfolio Segment [Member] | Commercial Mortgage [Member]                      
Balance       5,199       3,948 5,199 3,948  
Charge-offs                 (110) (50)  
Recoveries                 62 27  
Provision for loan and lease losses                 1,076 1,274  
Balance 6,227       5,199       6,227 5,199 3,948
Real Estate Portfolio Segment [Member] | Home Equity Loan [Member]                      
Balance       1,307       1,917 1,307 1,917  
Charge-offs                 (592) (774)  
Recoveries                 68 98  
Provision for loan and lease losses                 472 66  
Balance 1,255       1,307       1,255 1,307 1,917
Real Estate Portfolio Segment [Member] | Residential Mortgage Loan [Member]                      
Balance       1,740       1,736 1,740 1,736  
Charge-offs                 (306) (791)  
Recoveries                 48 35  
Provision for loan and lease losses                 435 760  
Balance 1,917       1,740       1,917 1,740 1,736
Real Estate Portfolio Segment [Member] | Construction Loans [Member]                      
Balance       1,324       1,367 1,324 1,367  
Charge-offs                  
Recoveries                 64 4  
Provision for loan and lease losses                 845 (47)  
Balance 2,233       1,324       2,233 1,324 1,367
Commercial Portfolio Segment [Member]                      
Balance       5,609       4,533 5,609 4,533  
Charge-offs                 (1,298) (1,220)  
Recoveries                 93 35  
Provision for loan and lease losses                 738 2,261  
Balance 5,142       5,609       5,142 5,609 4,533
Consumer Portfolio Segment [Member]                      
Balance       142       238 142 238  
Charge-offs                 (173) (177)  
Recoveries                 23 29  
Provision for loan and lease losses                 161 52  
Balance 153       142       153 142 238
Finance Leases Portfolio Segment [Member]                      
Balance       518       468 518 468  
Charge-offs                 (808) (442)  
Recoveries                 232 101  
Provision for loan and lease losses                 617 391  
Balance 559       518       559 518 468
Unallocated Financing Receivables [Member]                      
Balance       $ 18       $ 379 18 379  
Charge-offs                  
Recoveries                  
Provision for loan and lease losses                 (18) (361)  
Balance       $ 18       $ 18 $ 379