Note 13 - Other Comprehensive Income (Loss) - Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017
Balance	$ 366,500	$ 333,644		$ 313,872
Balance	406,297	366,500		333,644
Net current period other comprehensive income (loss)	5,819	(2,706)		(431)
Reclassification adjustment - ASU 2018-02		0
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance	(5,330)	(1,781)	[1]	(1,211)
Net current period other comprehensive income gain (loss)				(721)
Amounts reclassifed from AOCI				151
Balance	1,085	(5,330)		(1,781)	[1]
Net current period other comprehensive income (loss)	6,415	(3,053)
Reclassification adjustment - ASU 2018-02		(496)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance	408	193	[1]	(16)
Net current period other comprehensive income gain (loss)				209
Amounts reclassifed from AOCI				0
Balance	(37)	408		193	[1]
Net current period other comprehensive income (loss)	(445)	174
Reclassification adjustment - ASU 2018-02		41
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(220)	(342)	[1]	(272)
Net current period other comprehensive income gain (loss)				(70)
Amounts reclassifed from AOCI				0
Balance	(371)	(220)		(342)	[1]
Net current period other comprehensive income (loss)	(151)	173
Reclassification adjustment - ASU 2018-02		(51)
AOCI Attributable to Parent [Member]
Balance	(5,142)	(1,930)	[1]	(1,499)
Net current period other comprehensive income gain (loss)				(582)
Amounts reclassifed from AOCI				151
Balance	677	(5,142)		(1,930)	[1]
Net current period other comprehensive income (loss)	$ 5,819	(2,706)		$ (431)
Reclassification adjustment - ASU 2018-02		$ (506)

[1] December 31, 2017 AOCI component balances reflect a correction of incorrectly reported year-end balances in the Footnote titled "Other Comprehensive Income (Loss)" of the 2017 Form 10-K, which were presented as $(2,278), $234, and $(392) for securities AFS, cash flow hedges, and minimum pension liability, respectively.