Note 5 - Debt Securities - Summary of Volume of state and Political Subdivision Securities Held to Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Tax-exempt state and political subdivisions	$ 94,227	$ 96,163
Unrealized Gains	0	0
Unrealized Losses	5,908	9,536
Debt Securities, Held-to-maturity, Fair Value	88,319	$ 86,627
TEXAS
Tax-exempt state and political subdivisions	14,795
Unrealized Gains	0
Unrealized Losses	854
Debt Securities, Held-to-maturity, Fair Value	13,941
CALIFORNIA
Tax-exempt state and political subdivisions	9,450
Unrealized Gains	0
Unrealized Losses	454
Debt Securities, Held-to-maturity, Fair Value	8,996
PENNSYLVANIA
Tax-exempt state and political subdivisions	8,322
Unrealized Gains	0
Unrealized Losses	439
Debt Securities, Held-to-maturity, Fair Value	7,883
FLORIDA
Tax-exempt state and political subdivisions	7,331
Unrealized Gains	0
Unrealized Losses	637
Debt Securities, Held-to-maturity, Fair Value	6,694
MICHIGAN
Tax-exempt state and political subdivisions	6,772
Unrealized Gains	0
Unrealized Losses	503
Debt Securities, Held-to-maturity, Fair Value	$ 6,269

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

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