Note 3 - Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
BALANCE		$ 26,913	$ 24,828	$ 25,907	$ 23,836
BALANCE		27,857	25,548	27,857	25,548
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
BALANCE	[1]	6	15	20	(2)
Other comprehensive income before classifications	[1]	81	10	67	27
Amount reclassified from accumulated other comprehensive income	[1]
Total other comprehensive income	[1]	81	10	67	27
BALANCE	[1]	$ 87	$ 25	$ 87	$ 25

[1] All amounts are net of tax. Amounts in parentheses indicate debits.