Note 4 - Loans and the Allowance for Loan Losses - Changes in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Beginning balance	$ 6,430	$ 5,780	$ 6,078	$ 5,451	$ 5,451
Provision	200	300	600	900	1,100
Charge-offs	(227)	(222)	(757)	(672)	(827)
Recoveries	74	59	556	238	354
Ending balance	$ 6,477	$ 5,917	$ 6,477	$ 5,917	$ 6,078