Note 4 - Loans Receivable (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Unamortized Loan Cost (Fee)	$ 1,200,000	$ 1,700,000
Financing Receivable, Allowance for Credit Loss	7,571,000	8,345,000
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	895,157,000	1,059,106,000
Financing Receivable, Accrued Interest, before Allowance for Credit Loss	2,400,000	1,400,000
Financing Receivable, Modified, Accumulated	0	0
Real Estate or Business Assets [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	3,000,000	3,200,000
Equipment Finance Portfolio [Member]
Financing Receivable, before Allowance for Credit Loss	182,100,000
Small Business Equipment Finance [Member] \| Credit Exposure To 529 Obligors [Member]
Financing Receivable, before Allowance for Credit Loss	$ 23,000,000
Residential Mortgage [Member] \| First Mortgage [Member]
Percent Threshold On Loan To Value Ratios Requiring Private Mortgage Insurance	80.00%
Nonresidential Real Estate Loans [Member]
Projected Cash Flow To Loan Debt Service Requirement	120.00%
Mortgage Loans on Real Estate, Maturity (Year)	15 years
Loans and Leases Receivable, Amortization Period (Year)	25 years
Nonresidential Real Estate Loans [Member] \| Fixed Rate Nonresidential Mortgage [Member]
Loans and Leases Receivable, Amortization Period (Year)	15 years
U.S. Government 31 Departments or Agencies [Member] \| Equipment Finance Portfolio [Member]
Financing Receivable, before Allowance for Credit Loss	$ 43,800,000
Seventy Six State or Local Governments [Member] \| Equipment Finance Portfolio [Member]
Financing Receivable, before Allowance for Credit Loss	26,100,000
Middle-market Obligors and 214 Corporate [Member] \| Commercial Equipment Finance [Member]
Financing Receivable, before Allowance for Credit Loss	89,200,000
Commercial leases [Member]
Loans and Lease Receivables Outstanding Credit Exposure, Average Amount	791,000
Unfunded Loan Commitment [Member] \| Other Liabilities [Member]
Financing Receivable, Allowance for Credit Loss	$ 279,000	$ 335,000
Minimum [Member] \| Multi Family Mortgage Loans [Member]
Loan Amount To Appraised Value Of Property Securing Loan, Percentage	65.00%
Minimum [Member] \| Nonresidential Real Estate Loans [Member]
Loan Amount To Appraised Value Of Property Securing Loan, Percentage	65.00%
Maximum [Member] \| Multi Family Mortgage Loans [Member]
Loan Amount To Appraised Value Of Property Securing Loan, Percentage	75.00%
Maximum [Member] \| Nonresidential Real Estate Loans [Member]
Loan Amount To Appraised Value Of Property Securing Loan, Percentage	75.00%
Maximum [Member] \| Equipment Finance [Member]
Commercial Leases Maturity (Year)	5 years
Maximum [Member] \| Commercial leases [Member]
Loans And Lease Receivables, Outstanding Credit Exposure	$ 20,000,000
Weighted Average [Member] \| Small Business Equipment Finance [Member] \| Credit Exposure To 529 Obligors [Member]
Financing Receivable, before Allowance for Credit Loss	35,000
Weighted Average [Member] \| U.S. Government 31 Departments or Agencies [Member] \| Equipment Finance Portfolio [Member] \| Ten Largest Exposures [Member]
Financing Receivable, before Allowance for Credit Loss	2,300,000
Weighted Average [Member] \| Seventy Six State or Local Governments [Member] \| Equipment Finance Portfolio [Member] \| Ten Largest Exposures [Member]
Financing Receivable, before Allowance for Credit Loss	246,000
Weighted Average [Member] \| Middle-market Obligors and 214 Corporate [Member] \| Commercial Equipment Finance [Member] \| Ten Largest Exposures [Member]
Financing Receivable, before Allowance for Credit Loss	$ 292,000
Collateralized Loan [Member] \| Multi Family Mortgage Loans [Member]
Collateralized Loan Receivable, Percentage Of Collateral Located Outside Primary Market Area	40.00%
Projected Cash Flow To Loan Debt Service Requirement	120.00%
Collateralized Loan [Member] \| Minimum [Member] \| Multi Family Mortgage Loans [Member]
Financing Receivable, before Allowance for Credit Loss	$ 250,000
Collateralized Loan [Member] \| Minimum [Member] \| Nonresidential Real Estate Loans [Member]
Financing Receivable, before Allowance for Credit Loss	250,000
Collateralized Loan [Member] \| Maximum [Member] \| Multi Family Mortgage Loans [Member]
Financing Receivable, before Allowance for Credit Loss	8,500,000
Collateralized Loan [Member] \| Maximum [Member] \| Nonresidential Real Estate Loans [Member]
Financing Receivable, before Allowance for Credit Loss	$ 7,500,000

Percentage of collateral located outside primary market area for collateralized loan receivable.

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Represents maturity of commercial leases.

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Represents percentage threshold on loan to value ratios requiring private mortgage insurance.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of unamortized loan commitment, origination, and other costs (fees) on financing receivable recognized as adjustment to yield. Excludes financing receivable covered under loss sharing agreement.

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