Note 4 - Allowance for Credit Losses (Details Textual) Pure in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jan. 01, 2023 USD ($)
Financing Receivable, Modified, Accumulated	$ 0	$ 101
Financing Receivable, Modifications, Number of Contracts		0
Financing Receivable, Modified, Subsequent Default		$ 0
Financing Receivable Non-accrual Loans Excluded from Impaired Loan Disclosure	0	0
Financing Receivable, Nonaccrual, Interest Income	223	$ 177
Off-Balance-Sheet, Credit Loss, Liability			$ 0
Off-Balance-Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	260
Other Liabilities [Member]
Off-Balance-Sheet, Credit Loss, Liability	$ 413
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Off-Balance-Sheet, Credit Loss, Liability			$ 153

The carrying value of non-accrual loans excluded from impaired loan disclosure.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

+ References

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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Amount of interest income on financing receivable on nonaccrual status.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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