Note 4 - Investments - Amortized Cost to Fair Value of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Amortized cost	$ 3,014	$ 2,983
Unrealized gains	3	9
Unrealized losses	(7)	0
Fair value	$ 3,010	$ 2,992

Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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