Note 4 - Investments - Maturities of Debt Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
One year or less, Amortized Cost	$ 2,956	$ 2,432
One year or less, Fair Value	2,952	2,440
Greater than one year through five years, Amortized Cost	58	551
Greater than one year through five years, Fair Value	58	552
Amortized cost	3,014	2,983
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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