Note 3 - Investments, Held to Maturity (Details Textual)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	$ 135,200,000	$ 163,072,000
Debt Securities, Held-to-Maturity, Fair Value	$ 130,902,000	$ 158,540,000
Debt Securities, Held-to-Maturity, Weighted Average Yield	4.67%
Debt Securities, Held to Maturity, Unrealized Loss Position, Number of Positions	47	55
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss	$ 135,200,000	$ 163,072,000
Debt Securities, Held-to-Maturity, Allowance for Credit Loss	0
Debt Securities, Held-to-Maturity, 90 Days or More Past Due, Still Accruing	0
Debt Securities, Held-to-Maturity, Nonaccrual	0
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss	589,000
Commitments on Mortgage Loans [Member]
Debt Securities, Held-to-Maturity, Fair Value	8,900,000	14,300,000
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss	9,000,000	14,600,000
Asset Pledged as Collateral [Member] | Deposit Accounts, FHLB Advances and Other Borrowings [Member]
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss	94,100,000	107,500,000
Debt Securities, Held-to-Maturity, Fair Value	$ 89,800,000	$ 103,800,000