Note 7 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Due less than one year, amortized cost	$ 15,729
Due less than one year, fair value	15,602
Due after one year through five years, amortized cost	62,600
Due after one year through five years, fair value	62,067
Due after five years through ten years, amortized cost	235
Due after five years through ten years, fair value	236
Due after ten years, amortized cost	788
Due after ten years, fair value	612
No stated maturity, amortized cost	58
No stated maturity, fair value	130
Total, amortized cost	79,410	$ 79,839
Total, fair value	$ 78,647	$ 78,477