Note 9 - Income Taxes - Components of Income Tax (Benefit) Expense Recorded Directly to Stockholders' Equity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Unrealized (loss) gain on securities available for sale	$ 2,607	$ 1,757	$ (812)
Unrealized gain on derivatives	(27)	(120)	46
Minimum pension liability adjustment	(25)	(58)	46
Total income tax (benefit) expense recorded directly to stockholders' equity	$ 2,555	$ 1,579	$ (720)

The sum of the tax effects of all items occurring during the period that have been charged or credited directly to other comprehensive income or to related components of shareholders' equity.

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Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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