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Amount, before allowance for credit loss, of accrued interest on financing receivable.

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

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Note 4 - Loans Receivable (Details Textual) - USD ($)	12 Months Ended
Note 4 - Loans Receivable (Details Textual) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Unamortized Loan Cost (Fee)	$ 1,700,000	$ 1,600,000
Financing Receivable, Allowance for Credit Loss	8,345,000	8,129,000	$ 6,715,000
Financing Receivable, Accrued Interest, before Allowance for Credit Loss	1,400,000	38,000
Financing Receivable, Modified, Accumulated	0	$ 0
Equipment Finance Portfolio [Member]
Financing Receivable, before Allowance for Credit Loss	303,300,000
Small Business Equipment Finance [Member] \| Credit Exposure To 529 Obligors [Member]
Financing Receivable, before Allowance for Credit Loss	$ 32,200,000
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%
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	$ 82,300,000
U.S. Government 31 Departments or Agencies [Member] \| Equipment Finance Portfolio [Member] \| Ten Largest Exposures [Member]
Financing Receivable, before Allowance for Credit Loss	71,500,000
Seventy Six State or Local Governments [Member] \| Equipment Finance Portfolio [Member]
Financing Receivable, before Allowance for Credit Loss	50,000,000
Seventy Six State or Local Governments [Member] \| Equipment Finance Portfolio [Member] \| Ten Largest Exposures [Member]
Financing Receivable, before Allowance for Credit Loss	33,400,000
Middle-market Obligors and 214 Corporate [Member] \| Commercial Equipment Finance [Member]
Financing Receivable, before Allowance for Credit Loss	138,800,000
Middle-market Obligors and 214 Corporate [Member] \| Commercial Equipment Finance [Member] \| Ten Largest Exposures [Member]
Financing Receivable, before Allowance for Credit Loss	50,900,000
Commercial leases [Member]
Loans and Lease Receivables Outstanding Credit Exposure, Average Amount	814,000
Unfunded Loan Commitment [Member] \| Other Liabilities [Member]
Financing Receivable, Allowance for Credit Loss	$ 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%
Mortgage Loans on Real Estate, Maturity (Year)	3 years
Loans and Leases Receivable, Amortization Period (Year)	20 years
Maximum [Member] \| Multi Family Mortgage Loans [Member]
Loan Amount To Appraised Value Of Property Securing Loan, Percentage	80.00%
Maximum [Member] \| Nonresidential Real Estate Loans [Member]
Loan Amount To Appraised Value Of Property Securing Loan, Percentage	80.00%
Mortgage Loans on Real Estate, Maturity (Year)	5 years
Loans and Leases Receivable, Amortization Period (Year)	30 years
Maximum [Member] \| Equipment Finance [Member]
Commercial Leases Maturity (Year)	5 years
Maximum [Member] \| Commercial leases [Member]
Loans And Lease Receivables, Outstanding Credit Exposure	$ 24,000,000
Weighted Average [Member] \| Small Business Equipment Finance [Member] \| Credit Exposure To 529 Obligors [Member]
Financing Receivable, before Allowance for Credit Loss	53,000
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	3,200,000
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	819,000
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	$ 727,000
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	$ 500,000
Collateralized Loan [Member] \| Minimum [Member] \| Nonresidential Real Estate Loans [Member]
Financing Receivable, before Allowance for Credit Loss	500,000
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