Note 12 - Other Comprehensive Income (Loss) - Accumulated Other Comprehensive Income (Loss) by Component (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Balance	$ 333,644		$ 313,872		$ 286,519
Other comprehensive loss, net of tax benefit	(2,706)		(431)		(2,131)
Reclassification adjustment for adoption of ASU 2018-02
Balance	366,500		333,644		313,872
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Balance	(1,781)	[1]	(1,211)		965
Other comprehensive (loss) income before reclassifications	(3,053)		(721)		(2,176)
Amounts reclassified from accumulated other comprehensive income			151
Other comprehensive loss, net of tax benefit	(3,053)		(570)		(2,176)
Reclassification adjustment for adoption of ASU 2018-02	(496)
Balance	(5,330)		(1,781)	[1]	(1,211)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Balance	193	[1]	(16)		(60)
Other comprehensive (loss) income before reclassifications	174		209		44
Amounts reclassified from accumulated other comprehensive income
Other comprehensive loss, net of tax benefit	174		209		44
Reclassification adjustment for adoption of ASU 2018-02	41
Balance	408		193	[1]	(16)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(342)	[1]	(272)		(273)
Other comprehensive (loss) income before reclassifications	173		(70)		1
Amounts reclassified from accumulated other comprehensive income
Other comprehensive loss, net of tax benefit	173		(70)		1
Reclassification adjustment for adoption of ASU 2018-02	(51)
Balance	(220)		(342)	[1]	(272)
AOCI Attributable to Parent [Member]
Balance	(1,930)	[1]	(1,499)		632
Other comprehensive (loss) income before reclassifications	(2,706)		(582)		(2,131)
Amounts reclassified from accumulated other comprehensive income			151
Other comprehensive loss, net of tax benefit	(2,706)		(431)		(2,131)
Reclassification adjustment for adoption of ASU 2018-02	(506)
Balance	$ (5,142)		$ (1,930)	[1]	$ (1,499)

[1] December 31, 2017 AOCI component balances reflect a correction of incorrectly reported year-end balances in Note 12 of the 2017 Form 10-K, which were presented as $(2,278), $234, and $(392) for securities available for sale, cash flow hedges, and minimum pension liability, respectively.