Note 10 - FHLB Advances and FRB Borrowings (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 424.4	$ 388.3
Discount Window Borrowing [Member] \| Federal Home Loan Bank of Atlanta [Member]
Debt Instrument, Collateral Amount	381.0	72.6
Derivative Liability, Fair Value of Collateral	350.6	69.2
Debt Instrument, Face Amount	$ 119.2	$ 44.1
Long-Term Debt, Weighted Average Interest Rate, over Time	4.60%	4.50%
Federal Reserve Bank Term Funding Program [Member] \| Fed Funds Effective Rate Overnight Index Swap Rate [Member]
Debt Instrument, Basis Spread on Variable Rate	0.10%
Borrower-In-Custody Program [Member] \| Federal Home Loan Bank of Atlanta [Member]
Debt Instrument, Collateral Amount	$ 93.5
Derivative Liability, Fair Value of Collateral	65.5
Federal Home Loan Bank Advances [Member]
Debt Instrument, Collateral Amount	53.6	$ 70.1
Derivative Liability, Fair Value of Collateral	$ 44.1	$ 61.1

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount of assets pledged to secure a debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Fair value of securities pledged as collateral against derivative liabilities.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Weighted average interest rate of long-term debt outstanding calculated over time.

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