Note 6 - Accumulated Other Comprehensive Income - Changes in Accumulated Other Comprehensive Income (Loss) by Component, Net of Tax (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019		Jun. 30, 2020	Jun. 30, 2019
Balance		$ 132,687	$ 131,699		$ 137,775	$ 128,290
Total other comprehensive income		5,998	736	[1]	1,919	1,531	[1]
Other comprehensive income, before reclassification	[1]					1,681
Amount reclassified from accumulated other comprehensive income	[1]		(150)			(150)
Total other comprehensive income		5,998	736	[1]	1,919	1,531	[1]
Balance		140,695	134,260		140,695	134,260
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	[1]	(2,237)	641		1,842	(154)
Total other comprehensive income	[1]	5,998			1,919
Other comprehensive income, before reclassification	[1]		886
Total other comprehensive income	[1]	5,998			1,919
Balance	[1]	$ 3,761	$ 1,377		$ 3,761	$ 1,377

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