Note 11 - 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) - Fair Value, Nonrecurring [Member] - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Impaired loans	$ 1,928	$ 4,111
Other repossesed assets		35
Total assets	1,928	4,146
Fair Value, Inputs, Level 1 [Member]
Impaired loans
Other repossesed assets
Total assets
Fair Value, Inputs, Level 2 [Member]
Impaired loans
Other repossesed assets
Total assets
Fair Value, Inputs, Level 3 [Member]
Impaired loans	1,928	4,111
Other repossesed assets		35
Total assets	$ 1,928	$ 4,146