Note 5 - Debt Securities (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accrued Interest Receivable Debt Securities Available for Sale	$ 3,000	$ 2,300
State and Political Subdivisions Securities Number of States with Highest Volume	5
Debt Securities, Available-for-Sale, Total	$ 405,201	401,103
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Ending Balance	0
Accrued Interest Receivable Debt Securities Held to Maturity	1,100	1,100
Debt Securities, Held-to-Maturity, Nonaccrual	0	0
Proceeds from Maturities, Prepayments and Calls of Held-to-Maturity Securities	0	0	$ 1,000
Asset Pledged as Collateral [Member]
Debt Securities, Available-for-Sale, Total	$ 238,600	$ 234,300
Residential Mortgage-Backed Securities [Member] \| Minimum [Member]
Debt Securities, Available for Sale, Contractual Maturity, Term (Year)	2 years
Debt Securities, Available for Sale, Estimated Average Life (Month)	6 months
Residential Mortgage-Backed Securities [Member] \| Maximum [Member]
Debt Securities, Available for Sale, Contractual Maturity, Term (Year)	49 years
Debt Securities, Available for Sale, Estimated Average Life (Month)	16 years
Securities Issuers Concentration Risk [Member] \| Securities, Total [Member] \| US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-Sale, Total	$ 0

Reprints accrued interest receivable debt securities available for sale.

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Represents accrued interest receivable debt securities held to maturity.

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The term of contractual maturity on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

No definition available.

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The estimated average life on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Represents state and political subdivisions securities number of states with highest volume.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status.

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The cash inflow associated with the maturity, prepayments and calls (requests for early payments) of debt securities designated as held-to-maturity.

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