Note 3 - Investment Securities (Details Textual)	12 Months Ended
Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 16,078,000	$ 17,275,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	2,873,000	3,501,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	49,704,000	52,819,000
Debt Securities, Held-to-Maturity, Unamortized Unrecognized Holding Loss from Transfer	0	0
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Excluding Accrued Interest	$ 0	0
Municipal Bonds [Member]
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions	5
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 2,700,000
Subordinated Debt [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 2,500,000	2,500,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions	1
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 215,000	0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	19
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 7,191,000	7,717,000
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	1,515,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	6
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 614,000	845,000
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	22
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 17,105,000	19,440,000
Taxable Municipal Bonds [Member]
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 0	0
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	11
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 8,201,000	8,307,000
Nontaxable Municipal Bonds [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	13,578,000	14,775,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 2,658,000	1,986,000
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	28
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 16,593,000	16,510,000
New Market Tax Credits [Member]
Amortization Method Qualified New Market Tax Credit Investments	9,400,000	3,100,000
Amortization Method Qualified New Market Tax Credit Investments Amortization	911,000	0	$ 0
Asset Pledged as Collateral [Member]
Debt Securities, Available-for-Sale, Restricted	394,000	16,100,000
Financial Asset, Equal to or Greater than 30 Days Past Due [Member]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 0	$ 0	$ 0

The amount of investment related to new market tax credits using proportional amortization method.

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The amount of amortization related to the new market tax credit investments.

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Amount before tax of the unamortized unrealized loss from transferring from available-for-sale securities to held-to-maturity securities.

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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), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of restricted 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, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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