Note 8 - Reclassifications Out of Other Comprehensive Income - Items Reclassified to Net Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Tax expense related to realized gains on securities sold	$ 232	$ 176	$ 379	$ 518
Net income	973	434	2,163	1,199
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Realized gains on sales of securities held for sale during the period consider available for sale		29	60	42
Tax expense related to realized gains on securities sold		10	13	14
Net income		$ 19	$ 47	$ 28