Note 12 - Investment Securities (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Investment Income, Amortization of Discount	$ 241	$ 51
Fair Value, Inputs, Level 1 [Member] \| Money Market Funds [Member]
Cash, Ending Balance	$ 2,943	$ 6,697
Maximum [Member] \| Held-to-maturity Securities [Member]
Debt Securities, Available-for-sale, Term (Year)	2 years

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Period between issuance and maturity of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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Amount of accretion of purchase discount on nonoperating securities.

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