Note 9 - Fair Value of Financial Instruments - Assets and Liabilities Carried at Fair Value on a Non-recurring Basis, and the Method Used to Determine Their Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value	$ 20,159	$ 15,501
Impaired Loans [Member]
Fair Value	20,159	14,968
Other Real Estate Owned [Member]
Fair Value		533
Fair Value, Inputs, Level 1 [Member]
Fair Value
Fair Value, Inputs, Level 1 [Member] | Impaired Loans [Member]
Fair Value
Fair Value, Inputs, Level 1 [Member] | Other Real Estate Owned [Member]
Fair Value
Fair Value, Inputs, Level 2 [Member]
Fair Value
Fair Value, Inputs, Level 2 [Member] | Impaired Loans [Member]
Fair Value
Fair Value, Inputs, Level 2 [Member] | Other Real Estate Owned [Member]
Fair Value
Fair Value, Inputs, Level 3 [Member]
Fair Value	20,159	15,501
Fair Value, Inputs, Level 3 [Member] | Impaired Loans [Member]
Fair Value	20,159	14,968
Fair Value, Inputs, Level 3 [Member] | Other Real Estate Owned [Member]
Fair Value		$ 533