Note 7 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Due less than one year, amortized cost	$ 7,356
Due less than one year, fair value	7,303
Due after one year through five years, amortized cost	70,258
Due after one year through five years, fair value	69,568
Due after five years through ten years, amortized cost	2,257
Due after five years through ten years, fair value	2,255
Due after ten years, amortized cost	767
Due after ten years, fair value	661
No stated maturity, amortized cost	145
No stated maturity, fair value	145
Total, amortized cost	80,783	$ 81,502
Total, fair value	$ 79,932	$ 79,980