Note 7 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Due less than one year, amortized cost	$ 1,308
Due less than one year, fair value	1,307
Due after one year through five years, amortized cost	74,872
Due after one year through five years, fair value	74,195
Due after five years through ten years, amortized cost	2,005
Due after five years through ten years, fair value	2,001
Due after ten years, amortized cost	877
Due after ten years, fair value	702
No stated maturity, amortized cost	58
No stated maturity, fair value	146
Total, amortized cost	79,120	$ 79,839
Total, fair value	$ 78,351	$ 78,477