Note 2 - Summary of Significant Accounting Policies - Amortized Cost to Fair Value of HTM Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Amortized cost	$ 19,043	$ 15,800
Gross unrecognized gains	115	0
Gross unrecognized losses	(12)	(86)
Fair value	$ 19,146	$ 15,714

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).

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