Note 16 - Components of Accumulated Other Comprehensive Income (Loss) - Components of Accumulated Other Comprehensive Income (Loss) (Details) (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net pension gain (loss) arising during the period, taxes	$ 249	$ (115)	$ (132)
Amortization of prior service cost included in net periodic pension cost, tax	24	38	38
Transfer from held-to-maturity to available-for-sale securities, tax	237
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Unrealized holding gain (loss) on available for sale securities, tax	(595)	296	(431)
Reclassification adjustment for gain included in net income, taxes	(4)	(4)	(65)
Net pension gain (loss) arising during the period, taxes	0	0	0
Amortization of prior service cost included in net periodic pension cost, tax	0	0	0
Reclassification adjustment for gain included in net income, taxes	(4)	(4)	(65)
Transfer from held-to-maturity to available-for-sale securities, tax	237
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Unrealized holding gain (loss) on available for sale securities, tax	0	0	0
Reclassification adjustment for gain included in net income, taxes	0	0	0
Net pension gain (loss) arising during the period, taxes	(249)	115	132
Amortization of prior service cost included in net periodic pension cost, tax	(24)	(38)	(38)
Reclassification adjustment for gain included in net income, taxes	0	0	0
Transfer from held-to-maturity to available-for-sale securities, tax	0
AOCI Attributable to Parent [Member]
Unrealized holding gain (loss) on available for sale securities, tax	(595)	296	(431)
Reclassification adjustment for gain included in net income, taxes	(4)	(4)	(65)
Net pension gain (loss) arising during the period, taxes	(249)	115	132
Amortization of prior service cost included in net periodic pension cost, tax	(24)	(38)	(38)
Reclassification adjustment for gain included in net income, taxes	(4)	$ (4)	$ (65)
Transfer from held-to-maturity to available-for-sale securities, tax	$ 237

Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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