Note 5 - Loans - Impaired Loans (Details) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Recorded investment, with no allowance recorded $ 1,875 $ 3,486
Unpaid principal balance, with no allowance recorded 2,491 5,006
Recorded investment, with a related allowance recorded 3,729 4,475
Unpaid principal balance, with a related allowance recorded 3,729 4,475
Related allowance 302 381
Recorded investment 5,604 7,961
Unpaid principal balance 6,220 9,481
Real Estate Loan [Member]    
Recorded investment, with no allowance recorded 1,802 3,362
Unpaid principal balance, with no allowance recorded 2,386 4,850
Recorded investment, with a related allowance recorded 3,414 4,045
Unpaid principal balance, with a related allowance recorded 3,414 4,045
Related allowance 283 380
Recorded investment 5,216 7,407
Unpaid principal balance 5,800 8,895
Residential Portfolio Segment [Member] | Real Estate Loan [Member]    
Recorded investment, with no allowance recorded 386 1,042
Unpaid principal balance, with no allowance recorded 477 1,138
Recorded investment, with a related allowance recorded 1,543 1,888
Unpaid principal balance, with a related allowance recorded 1,543 1,888
Related allowance 29 92
Recorded investment 1,929 2,930
Unpaid principal balance 2,020 3,026
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]    
Recorded investment, with no allowance recorded 1,066 1,850
Unpaid principal balance, with no allowance recorded 1,143 2,868
Recorded investment, with a related allowance recorded 1,871 1,981
Unpaid principal balance, with a related allowance recorded 1,871 1,981
Related allowance 254 287
Recorded investment 2,937 3,831
Unpaid principal balance 3,014 4,849
Construction, Land Acquisition and Development [Member] | Real Estate Loan [Member]    
Recorded investment, with no allowance recorded 350 470
Unpaid principal balance, with no allowance recorded 766 844
Recorded investment, with a related allowance recorded 0 176
Unpaid principal balance, with a related allowance recorded 0 176
Related allowance 0 1
Recorded investment 350 646
Unpaid principal balance 766 1,020
Commercial and Industrial [Member]    
Recorded investment, with no allowance recorded 73 124
Unpaid principal balance, with no allowance recorded 105 156
Recorded investment, with a related allowance recorded 18 79
Unpaid principal balance, with a related allowance recorded 18 79
Related allowance 18 0
Recorded investment 91 203
Unpaid principal balance 123 235
Consumer Portfolio Segment [Member]    
Recorded investment, with no allowance recorded 0 0
Unpaid principal balance, with no allowance recorded 0 0
Recorded investment, with a related allowance recorded 297 351
Unpaid principal balance, with a related allowance recorded 297 351
Related allowance 1 1
Recorded investment 297 351
Unpaid principal balance 297 351
State and Political Subdivisions [Member]    
Recorded investment, with no allowance recorded 0 0
Unpaid principal balance, with no allowance recorded 0 0
Recorded investment, with a related allowance recorded 0 0
Unpaid principal balance, with a related allowance recorded 0 0
Related allowance 0 0
Recorded investment 0 0
Unpaid principal balance $ 0 $ 0