Note 22 - Fair Values - Losses Resulting from Non-recurring Fair Value Adjustments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Losses resulting from nonrecurring fair value adjustments	$ 58	$ 1,260	$ 673
Collateral Dependent Impaired Loans [Member]
Losses resulting from nonrecurring fair value adjustments	20	1,183	476
Other Real Estate Owned [Member]
Losses resulting from nonrecurring fair value adjustments	$ 38	$ 77	$ 197